Irrigation bags can be used well, but more often simply add misery to trees and aesthetics
Irrigation bags, often called “tree gators,” are durable plastic bags used for irrigating newly planted trees. These projects have been discussed here and here and I still don’t like them as they don’t consistently benefit trees and often create conditions conducive to pests and disease. Plus, as the blog title suggests, their aesthetic attributes are nonexistent.
Surprisingly, camoflauge green doesn’t actually camoflauge anything.
Newly installed trees and shrubs generally need to have supplemental water, period. It doesn’t matter if they are “drought tolerant” species – any plant needs sufficient water to establish roots. And where automated irrigation systems aren’t possible, there are many products that promise to deliver water to the establishing root system. Unfortunately, they often deliver other things as well, including pests, disease, and early death.
To
be fair, many time these trees die because they were poorly planted: we know
that improperly amended soils, structurally compromised root systems, inadequate
root preparation, and/or poor installation are the leading causes of young tree
failure. But anything that covers the trunks of young trees and reduces air
flow and light exposure will, over time, create a dark, moist, and reduced
oxygen environment that’s damaging to the bark of young trees. Wet, damaged
bark allows opportunistic pests and pathogens to invade.
Each one of these bags delivers water outside the planting hole, which encourages root growth outwards.
Until a few weeks ago, I had not seen any irrigation bags that I actually thought might work. These bags are installed on stakes away from the tree trunks, and they deliver water to the area where tree roots need to grow, enhancing root establishment. It took a trip to Malmö, Sweden to see this innovative approach and my immediate reaction was “why hasn’t anyone thought of this before?”
Various tree irrigators of dubious value. Note presence of weeds and/or lack of water in devices.
There are many types of irrigation bags, from sleeves to donuts, but none of them are as good for tree or soil health as a thick layer of arborist wood chips. When wood chips can’t be used for some reason, irrigation bags set well away from the tree and actually kept full of water might be a good solution.
Arborist wood chips provide a highly absorbant matrix that releases water slowly into the root zone.
What do the words on your food (or garden supplies) labels mean? Do you know the difference between organic, natural, and sustainable? Are there rules about who can use which labels? When you are shopping at the farmers market or grocery store, or when you’re buying seeds or plants at the garden center, it is important to know what the words used to describe the product mean. It is also important to understand that some words have different meanings to different people and sometimes are used more for marketing (and sometimes misleading customers) than conveying actual meaning. Let’s take a look at some of the words that have an “official” definition, some where the meaning can be interpreted differently, and some that can be misleading or misinterpreted.
“Official” words for foods and plants
There are a handful of words that you’ll find at the grocery store, farmers market, or garden center that have an official definition because they are either part of a law or code or are part of an official certification process.
For example, in the US for a product to bear the term “certified organic” or “organic“, it must be produced in accordance with the National Organic Program organic certification process outlined in federal policy/law and administered by the USDA. While there are many minute details for organic production, the “big picture” definition is that only organic/naturally occurring soil amendments and pesticides can be used – typically from a biological or elemental source. It is important to note that organic does not mean pesticide free. Repeat: ORGANIC DOES NOT MEAN PESTICIDE FREE
The organic certification process can be costly and time consuming, and some producers feel that restrictions do not go far enough, so alternative certifications have been developed such as Certified Naturally Grown and Regenerative Organic Certified. These certifications are not administered by the USDA, but rather by individual organizations that have developed them.
Another term that has emerged is “biodynamic,” which marries some organic principles with the requirement that the farm be a “closed system”, meaning that outside inputs like fertility are not used. Biodynamic production also requires the use of “preparations” that would be described as mystical or homeopathic and must be practices in accordance with “energies” such as the phase of the moon. In order to be labeled “biodynamic” a product must be certified by Demeter USA. Our very own LCS has addresses the “pseudoscience” of biodynamic growing in a previous paper. As a science-based group, we consider biodynamic to mainly be WOO.
A number of other certifications exist, such as Certified Animal Welfare Approved and Salmon Safe that guarantee things like best practices in livestock welfare and proper wild fishing practices.
“Unofficial” words for growing and marketing
While “official” words have certifications that standardize their meaning across industries, other words we use for production and marketing don’t have official meanings and are often up for interpretation. In instances where a relationship exists between a consumer and producer, say a customer buying directly from a farmer at the farmers market, a conversation can take place to share the meaning of what the words mean. In situations like a product at the grocery store, words are often left to the interpretation of the customer.
For example, while the term “organic” or “certified organic” requires official certification, using the term “organically grown” does not. Many small farmers will use this term to reflect their use of organic practices, but their understanding of practices may deviate from the “official” definition. The term natural or naturally grown may also be used to describe produce or products at the grocery store but no officially sanctioned definition exists. When customers and growers/producers can discuss what the terms mean, an understanding can be developed. However, when such a relationship doesn’t exist, it is hard to know what the terms mean. For example, an ad might say that a product is “natural, so you know that it’s good” to which I might joke that poison ivy and rattlesnake venom are both natural, but that doesn’t mean it is good for you.
The term “local” also doesn’t have a specific definition and can vary widely depending on the context. At farmers markets, it is up to the organization operating the farmers market to create vendor rules and decide what makes sense for each individual market, according to the national Farmers Market Coalition. For example, the closest meat producer may be farther outside of the city than the closest produce farmer. Markets in urban areas may need to recruit vendors from a bit farther away than those in the suburbs. If you have questions about the rules of your local market or where a vendor is farming – just ask! At a grocery store, local can mean whatever the chain wants to decide. Sometimes this can mean in the same state or other times it is regional. Often food at the grocery store will have a label saying the town or region it came from for you to learn more about each specific item.
Is it “local”? Depends on who you ask.
The terms sustainable and regenerative might be used to describe production practices or a farmer’s philosophy on production. While there aren’t official definitions, the USDA Sustainable Agriculture Research and Education program defines sustainable agriculture as holistic farming practices that balances environmental stewardship, profitability, and personal/social benefit. Though most use of the term sustainable for marketing focuses on the environmental aspect. Regenerative agriculture is a relatively new philosophy of production practices that focus on environmental stewardship to reverse climate change and/or environmental degradation and social fairness and often involves improving soil health. While the terms sustainable and regenerative might seem interchangeable, there are differences (mainly around economic sustainability and around maintaining current environmental conditions vs. improving them). We’ll see how the “regenerative” term plays out – as many consider it to be a “buzzword” in some ag circles.
Words that can confuse or mislead
While there are words that may seem abundantly clear to the person using them, the information or intent may seem totally different to the audience. These words are often used as buzzwords for marketing or may be used to create a sense of fear that is misunderstood. For these words, alternative words or further explanation might reduce confusion.
One such word that is often used is chemical-free. This is often used to describe produce or food that is produced without pesticides. However, use of chemical-free can be misinterpreted and misunderstood. It may be a facetious response, but as a scientist I often cringe when I hear this word used at the farmers market because that I know that everything is made of chemicals – all rocks, plants, animals, humans, and even air and water – are chemicals. Some say that the use of this term is based in fear of pesticides (even organic ones) or is based in anti-science “chemophobia” rhetoric. Using a more precise term, such as pesticide-free conveys the same message without anti-science connotations and reduces the chance of misinterpretation.
Non-GMO is also another term that was created as a fear-based marketing term that has become pervasive at the grocery store, the seed rack, and the farmers market. While there are concerns AND benefits to genetic engineering technology, use of the term non-GMO is often redundant and confusing to consumers because, as it turns out, there are very few opportunities for gardeners, farmers, or consumers to interact with bioengineered crops. Most bioengineered crops are those that are produced as commodities – field corn, soybeans, sugar beets, cotton, canola, etc. Only a handful of crops are those that you’d find at the farmers market or produce section – sweet corn, summer squash, papaya, and one apple cultivar. But these crops are grown in very small amounts, are not available to small-scale farmers or home gardeners, are sold only in larger quantities, and require a contract for purchase. Most produce items grown in the US do not currently have a genetically engineered counterpart – there are no GMO lettuces, radishes, etc. So labeling a tomato as non-GMO is redundant and has unfortunately caused so much confusion and fear amongst consumers that many specifically demand or seek non-GMO tomatoes, even though all tomatoes are non-GMO. There is a third-party certification process through the Non-GMO Project (they’re the ones you see with the butterfly logo on almost every product, even bottled water and salt), however given the confusion and misinformation around the term, the US government recently created a standard “Bioengineered” labeling requirement for all produce and products that consist of or contain genetically engineered crops or ingredients.
A few more words on words…
While words can inform and confuse, being an educated consumer (or producer) can help reduce confusion and help us understand the food that we eat. While we haven’t covered every word you might encounter on a label here, researching words you see can help build your label vocabulary. Building interest in learning about where your food comes from should be a fun way to connect with what is on your plate and who is in your community. Go out there and enjoy the learning process! You can check out some more words related to agriculture and food here.
A bee lawn is a way to benefit pollinators in our landscapes by providing additional floral resources, and often utilizes a mix of low-growing flowering plants in addition to turf species. Although flower gardens also provide flowering plants for pollinators, bee lawns can be multi-functional in their usability for recreational purposes with the added benefit of providing food for bees.
Habitat loss is one of the major factors implicated in the global declines of native bee species. Providing resources utilized by these critical pollinators can assist in mitigating this. Research through University of Minnesota has found 50 species of bees utilizing the flowers in bee lawns.
The purpose of bee lawns includes providing nutritious sources of nectar and pollen for pollinators, especially in urban environments, where these resources can often be scarce and difficult to find. Additional factors include recreational usability, and reducing inputs, e.g., irrigation, nutrients, weed control, and time spent mowing. Flowering plants suited for bee lawns have a variety of common characteristics including: low-growing and flowering heights, perennial life cycles, the ability to persist with turf species, and tolerance of mowing and foot traffic.
An important consideration is that bee lawns don’t necessarily mean weedy lawns or no-maintenance lawns, but instead require different types of management and serve different functions than traditional turfgrass lawns.
Not all bee lawns are created equal, and some work better
than others.
Here are some turfgrass species that can work
well for bee lawns:
Cool-season turf
A mix of fine fescues (which includes species such as:
creeping red fescue, chewings fescue, hard fescue, and sheep fescue) are some
of the best options for bee lawns due to reduced needs for inputs including
irrigation, fertilizer, and weed controls, in addition to their compatibility
with flowering plants. That being said, fine fescues do not tolerate heavy foot
traffic, and may not be a suitable option for turf varieties in areas with
heavy recreational use.
Kentucky bluegrass (KBG) is another option for bee lawns, though it requires higher maintenance (including more frequent irrigation and fertilizer inputs). KBG is considered an invasive species in some areas so do your homework.
Warm-season turf
Although there is limited research currently available for
warm season turfgrasses and their compatibility with flowering plants specifically
for bee lawns, certain species require lower inputs and could be a good option.
Centipede grass is a suitable option for a low-maintenance
warm season turf species, and has been utilized in studies evaluating
early-spring flowering bulbs as part of a lawn ecosystem for pollinators (see
resources for more information).
Bermudagrass can also be used with flowering plants, though it has higher input needs than centipede grass. For more detailed information on warm season turfgrass species suitable to your geographic area and their respective input needs, I would encourage you to reach out to your local and regional extension offices.
Here are examples of flowering plants that can work
well with turfgrass species:
Dutch white clover (Trifolium repens)
Dutch white clover (often referred to as white clover or clover) is a common occurrence in many lawns. Although some consider this to be a weed, white clover can provide several benefits including its adaptability to many soil types, the ability to withstand some shade and foot traffic, and the added benefit of being able to fix its own nitrogen. Like its name suggests, white clover produces white (and sometimes pink) flowers, and grows to a height of 4-6 inches. In addition to its hardiness, white clover is also an excellent source of forage for bees due to its long bloom time, and the great quality of nectar (high sugar content) and pollen (high protein content).
Dutch white clover flowers in a lawn (Photo: Whitney Cranshaw, Colorado State University, Bugwood.org)
Creeping thyme (Thymus praecox)
Creeping thyme is related to some of our favorite culinary
herbs, and produces fragrant purple/pink flowers. It has a low growth habit (<6
inches) and can tolerate some foot traffic. It performs best in well-drained
sandy or loamy soils, and is also considered to be drought tolerant and
deer-resistant.
Self-heal (Prunella vulgaris ssp. lanceolata)
Self-heal is native to North America, Europe and Asia, and research from University of Minnesota has shown that 95% of the pollinators that visited the flowers were native bee species. It produces purple flowers and does well in a variety of soil types (with the exception of sandy soils) and in sun or partial shade.
Self-heal flowering with turfgrass (Photo: John D. Byrd, Mississippi State University, Bugwood.org)
Common violet (Viola sororia)
Violets are another flower that some consider to be a weed in home lawns. These spring blooming yellow, purple, and white flowers can be a good source of nectar for pollinators such as butterflies and bees. Violets grow to heights of 4-8 inches, and do well in a variety of soil types in addition to sun and shade.
Violets growing in a lawn (Photo: Sarah Eilers, Montana State University)
Other flowers
Additional low-growing flowers could also be great additions to bee lawns, including early spring flowering bulbs that can persist with turfgrass for multiple years, such as crocus and grape hyacinth (Muscari spp.), which have been observed to attract pollinating insects (especially honey bees).
For more information on the regional suitability of
flowering plants to incorporate with turfgrass for bee lawns, contact your
local extension offices for more information.
Larson, J. L., Kesheimer, A. J., & Potter, D. A.
(2014). Pollinator assemblages on dandelions and white clover in urban and
suburban lawns. Journal of Insect Conservation, 18(5), 863-873. https://link.springer.com/article/10.1007/s10841-014-9694-9
In my last
blog post in early August, I noted how quiet the Atlantic tropical season
has been so far this year. In fact, the period from early July through this
week has been one of the quietest on record, with no named storms since the short-lived
Tropical Storm Colin formed along the South Carolina coast and dissipated less
than 24 hours later on July 3 in eastern North Carolina. The last time we had
so few named storms was 40 years ago, so while it is not unprecedented, it is
certainly unusual. And we are definitely later than the average date for the
first hurricane of the year. By comparison, in 1992, a strong El Niño
year, Hurricane Andrew (an “A” storm, so the first of the year) had formed and taken
its devastating track through southern Florida and Louisiana by this date.
Atlantic 5-day outlook on 8-28-2022
All of that is about to change, and hurricane forecasters are relieved after predicting a season of above-normal activity based on warm ocean temperatures and the current strong La Niña. They could still be correct. The National Hurricane Center’s 5-day map (as of 8-28-2022) is now showing four areas of potential development, with one area that has a 50% chance of development into a tropical depression within the next 5 days. Just in time for the peak of the season, according to the timeline we discussed earlier this month.
Why have the tropics been so quiet?
What caused the very quiet period in July and August? Hurricane
climatologists point to several factors: the continuing clouds of dust that
have blown off Africa and across the Atlantic Ocean towards the west, dry air
moving in from Europe, which is experiencing its worst drought in 500 years,
and the lack of strong waves moving off of Africa to act as seeds for tropical
storm development. But the presence of warm sea surface temperatures and the
lack of a strong jet stream (which is consistent with the presence of the La Niña)
were expected to contribute to a stronger season than we have seen so far. If
we can’t understand why this season has been so quiet so far, it means we still
have a lot to learn about hurricane climatology and behavior.
Tropical Storm Lisa on September 23, 2016 with African dust
The second half of the 2022 season is likely to be a lot
more active than the first half, although forecasters have dropped the
predicted number of storms from the early forecast due to the past two quiet
months. If you live in an area affected by Atlantic hurricanes, you should be
prepared for a more active pattern—don’t let the last two months fool you! If
you live in another part of the world that is affected by tropical storms, you should
also understand their climatology and likely impacts on where you are as well.
Caribbean rain shower at Man-of-War Bay, Tobago, September 1980. Source: NOAA.
Some resources for following hurricane weather
For those of you who are fascinated by tropical storms and hurricanes, even if you don’t live in an area that is prone to them, there are a few resources that you can use to track potential storms and follow them as they develop and move through areas that could be severely impacted by them. The first site I use is the National Hurricane Center, the source of official forecasts and outlooks for the season as well as specific storms as they form. Their website has a lot of information about past storms as well as educational resources on tropical systems. You can also find a lot of maps and climatological information at Mike’s Weather Page if you just need a quick look at maps and other images related to tropical weather in the Atlantic and Pacific Basins.
On social media, I follow Bryan Norcross and Brian McNoldy
on Facebook and Twitter; they may be on other social media as well. Bryan
Norcross is the television meteorologist who was working in Miami at the time
of Hurricane Andrew; it has been fascinating this week to follow his timeline
of Andrew from tiny disturbance to monster storm as it hit Miami and then
Louisiana over the past week back in 1992, thirty years ago. Brian McNoldy is a
senior hurricane researcher who works at the University of Miami and has done
some interesting climatological work on past hurricanes as well as provides
insight on the current season. There are also plenty of great local resources
for local impacts if you live in a hurricane-prone area.
Landfall of Hurricane Michael, October 10, 2018 from earth.nullschool.net
How to visualize the wind
If you are interested in looking at the wind patterns
associated with storms, both tropical and extra-tropical, then there are three
sources of fascinating maps that allow you to visualize the flow of air across
the United States or the world:
United States current surface winds Hint.fm/wind. This site has a current map of
the surface winds across the continental United States showing the wind speed
and direction in motion. It is based on a near-real-time computer simulation to
provide seamless coverage across the country.
Global earth interactive wind map https://earth.nullschool.net/.
This interactive map allows you to look at current winds anywhere on the earth
by dragging and zooming on the globe. You can use the menu on the lower left to
pick higher levels in the atmosphere; this will allow you to look at jet
streams aloft as well as surface winds.
Windy global current and forecast winds https://www.windy.com/. This site provides
global current and forecast winds as well as other weather information that
will allow you to view the weather and plan for future weather conditions at
home or away.
These sites provide you with information about both wind speed and direction. That can be very useful for gardeners who are spraying or need wind information to track where the air hitting their gardens has come from. Wind drift of agricultural chemicals also causes damage to crops and outdoor workers. Exposure to chemicals such as weed killers can affect gardens adversely, and it can be important to know where those chemicals are coming from. If you don’t have access to local wind observations, these maps can provide you with useful information.
In this episode of P&P we’ll take a look at the life and career of the aptly named Nehemiah Grew, the “Father of Plant Anatomy”.
Nehemiah Grew 1641-1712
Nehemiah Grew was born on September 26, 1641 in Warwickshire, UK. He graduated from Pembroke College, Cambridge in 1661 and ten years later was awarded a MD degree from Leiden University in the Netherlands. His interest in plant anatomy began to bud in 1664. In 1670 his essay, The Anatomy of Vegetables begun, was shared with the Royal Society and resulted in his election to the membership. By 1672 he’d put down roots in London and soon had a large medical practise. Even though he was busy with his career as a physician he still found time over the next decade to write a couple of books, a few short publications on botany and several papers one of which has the intriguing title, “Comparative Anatomy of Stomachs and Guts” and was included in his “Catalog and Description of Rarities” publication, ca. 1681.
Photo courtesy of Royal Society (Great Britain) Museum.
In 1682 his tome, “The Anatomy of Plants begun as a philosophical history of plants“, was published. It’s largely a collection of previous publications and is divided into four books, Anatomy of Vegetables begun, Anatomy of Roots, Anatomy of Trunks and Anatomy of Leaves, Flowers, Fruits and Seeds. It has eight-two illustrated plates and an appendix of seven papers which deal mainly with chemistry. The book is noted for its descriptions of plant structure, a fairly unknown thing at that time. Grew described nearly all the key differences of stem and root morphology and showed that the flowers of the Asteraceae family are composed of multiple tiny tube flowers (florets). The most amazing of his discoveries was that plants reproduce sexually and that flowers are sexual organs. He distinguished and assigned “roles” to the calyx, corolla, pistils, and stamens.
Grew is remembered for being one of the first to establish the observational basis for botany and is noted for his detailed descriptions of plant anatomy. He utilized the microscope (invented in 1590) for his plant anatomy explorations and was a pioneer in this field. His book “Anatomy of Plants…” contains the first known microscopic description of pollen. He discovered that although all pollen is roughly globular, its size and shape varies between species; however pollen grains within a species are all alike. This discovery is central to the field of Palynology, “the study of dust”, which is the study of pollen and particulate samples both organic and inorganic.
Plate from Nehemiah Grew’s The Anatomy of Plants (1682) Source
Grew’s research technique was based on his adherence to observations and avoidance of explanations invoking occult, hidden or vital forces, or signatures. He also avoided the direct hand, intervention, or guidance by God or other spiritual beings. He embraced a mechanical and natural philosophy which permitted him to think much like an engineer or how to make the most out of the materials at hand. This engineering concept was theologically acceptable during his time. Why is this significant? This ‘Mechanical way’ and Grew’s own theory of “Organ-ism”, that plants possess organs and structure, was outside the bounds of most of the thinking of his time. Before the 17th century it wasn’t certain that plants had much internal structure and that distinct parts or organs played distinct roles. It was often thought that the external shape of a plant was a clue or signature to its use, re: Doctrine of Signatures. But whether there was anything resembling organs in plants was contested. Grew’s detailed illustrations help dispel that belief and bring the study of plants into the scientific world.
Plate from Nehemiah Grew’s The Anatomy of Plants (1682) Source
In honor of Nehemiah’s work and role as a founder of modern botany, Carl Linnaeus named the genus Grewia after Nehemiah Grew. Grewia is in the Malvaceae family and can be found in several areas including Africa, India, and Australia where it has naturalized and become invasive. Its fruit comes in both sweet and tart varieties and is used for food and beverages. Other parts of the plant have been used medicinally.
I love a fair! Which is a good thing since I find myself at a lot of them as an extension professional. It seems like fairs attract extension folks like honey attracts flies. We’re always involved in the 4-H activities – the livestock, project displays, and contests. Sometimes we pop up other places as well. The one thing that I get asked to do multiple times each summer is act as a judge for horticultural entries. Usually for 4-H youth entries, but sometimes for the open class where anyone can enter their best (or sometimes not so best) produce, flowers, and more. I thought I’d take a few moments to talk about what I look for as a judge, so if you ever want to enter your best tomatoes or dahlias at the fair you’ll know what to do to get the best ribbon possible. And even if you aren’t going to enter something into the fair, the rules and guidelines we use can help you select quality seeds and plants for your own garden or help you pick out the best produce at the grocery store or farmers market.
Produce items and flowers with their ribbons after judging. Each item is judged on its own merits and is not compared to the other entries (except for selection of a “grand champion” or for submission to the state fair).
The fact is, many of the same qualities I look for and skills I use when judging produce and flowers at the county fair are also ones I use as a trial judge for the All-America Selections (AAS) program. I recently attended the AAS/National Garden Bureau/Home Garden Seed Association summer summit and was discussing fair judging with some folks from seed companies. They were excited by the process, and especially by the fact that one of the things that I judge (and have gotten fairly strict about) is that the fair entry information contain the cultivar or variety name. They found this exciting because companies, especially smaller companies, put a lot of work into developing new cultivars, and when the general public identifies specific cultivars as being high quality (as in, I grow XXXX cucumbers because I think they are the best) or at least being able to identify the qualities of specific cultivars then it is sort of like a recognition of the plant breeders and distribution company’s work (and also puts money in their pockets). As home gardeners, it is important to know which cultivars or varieties work best for you and to be able to identify the qualities you prefer. It can also be handy to see cultivars out in “the wild” and be able to recall the name of plants you like, which is why the All-America Selections program has display gardens where you can see the edible and ornamental winning plants up close and personal. I’ve written about the trial process for this blog before.
Our display garden on the UNL Campus, which is our home garden for our TV show Backyard Farmer. We feature the garden each week on the show, which is one of the longest running locally produced shows in the US celebrating its 70th anniversary this year. Watch episodes.
Now back to the fairs – this year I used my judgmental eye at five county fairs in the course of three weeks – with three of those fairs in one week. I’m not sure why I’m so popular, maybe because I’m good at it or maybe because nobody else will do it. In either case, I do my best to not only judge fairly and by the rules, but also provide valuable feedback as a learning opportunity for youth. The whole point of fair entries and projects, from our point of view at extension, is not that a kid gets a blue ribbon (in Nebraska the top standard ribbon is purple, though, which I had to adjust to) but that we help raise blue ribbon kids. In some counties I actually talk to kids, interviewing them on how they grew stuff and giving them feedback on their entries. When I don’t interview, I fill out a score sheet and provide comments on positives and negatives of each entry.
Here are a few of the things that I look for when judging,
and how they might help home gardeners:
Overall quality, appearance, and health – this is the one that most can identify with. Does the produce item or flower look appealing and high quality. Is it free of blemishes, diseases, bug holes, etc. You’d be amazed at the quality of some things we get at the fair. Of course, since I usually judge items for kids I do try to provide feedback on how to improve quality overall. Basically, my reference point is “would I buy this at full price a the market or grocery store”.
Correct preparation – this is one where lots of folks get tripped up. For produce items we are often looking for whether or not the item has been harvested correctly, whether or not the stem has been removed or trimmed properly. It varies by produce item. These rules seem superfluous and overkill, but they actually are based on guidelines for how to best prepare produce and flowers to extend their shelf life and storability. For example, in Nebraska our guide says to leave a ¼” piece of stem on cucumbers, to remove the blossom cap/stem (sepals) from tomatoes to reduce damage to fruit, to trim beet stems to 2”, to pull (not cut) rhubarb and leave 2” of the leaf blade attached, and so on and so forth. These guidelines all help reduce damage to produce items or keep them fresher longer – so these guidelines can be handy for home gardeners, too. Herb stems are to be cut a certain length and kept in water (like a bouquet) with the leaves below the water line removed. For flowers, rules will often state how large of a specimen to provide, and to remove the leaves below the water line. Rules vary by state and by fair, but many of them are fairly consistent here. You can find our Nebraska preparation guides for produce and flowers to see how best to harvest and prepare crops and flowers for storage or usage.
Uniformity of size, shape, color, etc. – this one also trips a lot of people up. First, most fair rule books will state a specific number of one item that needs to be provided, so that a judge may judge consistency and uniformity across multiple specimens. For example, our fairs require two specimens of larger produce items (slicing cucumber, zucchini, eggplant, etc), five specimens of medium size items (slicing tomatoes, carrots, potatoes, pickling cucumbers, beets, etc.), and twelve specimens of small items (cherry tomatoes, string beans, etc.). Flowers usually require five stems, but larger specimens like sunflowers may only require three. All the specimens provided in the exhibit should be as uniform as possible. All of the produce items and flower stems should be exactly the same size. Being the same level of maturity is also important and also leads to uniformity of color, especially in produce items. Color uniformity is especially important in flowers. I use this uniformity rule when judging our AAS trials as well – do the plants perform consistently across the whole plant in terms of harvest or flower appearance. This is a useful skill for home gardeners as well, as you can judge how well a specific cultivar or variety performs for you. You want to grow plants that perform well and provide consistent produce or flowers and not plants that only produce a few good items here and there with questionable produce or flowers mixed in.
Correct identification and cultivar names – as I stated earlier, the correct identification of the plant (like don’t enter a jalapeno pepper as a bell pepper) and the cultivar or variety are important. Knowing what the actual end product is supposed to look like is helpful for gardeners to know what they are growing, understand the traits that they want in the plants, and how to select the seeds or plants with the traits they desire. That’s why the seed company reps got excited about this part – because having gardeners identify specific (newer) cultivars as the ones with the traits they want is important. It takes garden selection from “I want a slicing tomato” to “I want this specific cultivar of tomato because I know it does X, Y, and Z, so I’ll buy it from this specific seed company that sells it. That in part is what we do with the All-America Selections trials. We try out new things (before they hit the market) to test them out for taste, color, disease resistance, and a whole bunch of other things to give a “stamp of approval.” So any time you see that AAS symbol you know there have been several judgmental eyes (including mine) have assessed those plants and found them worthy.
So next time you visit a fair take a look at the exhibits to see if you see what a judge looks for. And think about entering your produce or flowers in a fair near you just to see how your garden skills stack up with your neighbor’s. Even if you don’t win best of show you can have fun and learn a bit along the way. And even if you don’t enter at the fair, you can use your judgement to pick the best plants for your garden for years to come.
Sometimes you get to judge the “fun” stuff, too….like best dressed vegetable.
In the Southeast, almost nothing gets more press than the Atlantic Tropical Season, including the outlooks, real-time events, and post-storm analyses. If you live in another part of the United States or the world, you may not be as directly affected as the Southeast is, but you might be surprised at how far and wide tropical moisture is spread, either directly by tropical storms and hurricanes or by the remnant moisture which can be carried with the winds for long distances away from their original sources. This week I will describe what tropical systems are and what they mean for gardeners. In my next post, I will review the current season, including any impacts that have occurred. Don’t let the early quiet conditions fool you—about 90% of Atlantic tropical activity occurs from mid-August through mid-October.
I am using “tropical system” as a term that encompasses the
life cycle of a tropical disturbance from birth to death. That may include formation
by a tropical wave coming off Africa, developing in the Gulf of Mexico, or
growing in the Eastern Pacific Ocean, then a tropical storm, a hurricane (maybe
even a major one), and eventually a slow death as a tropical depression or extra-tropical
low that has lost its tropical characteristics.
The map below shows historical tracks for all known storms across the globe. Note that in some regions they are called hurricanes and others, typhoons, but both are tropical cyclones, the generic name for rotating, organized systems of thunderstorms that originate over tropical waters and have closed, low-level circulations. The pattern of tracks shows some interesting information about tropical systems. For example, why are there almost no tracks in the eastern part of the South Pacific Ocean or in the southern Atlantic? Why do many of the tracks show a curve as the storm moves from east to west? Why are there more storms in the Northern Hemisphere (NH) than in the Southern (SH)? Why are there almost no tracks along the equator?
Historical tropical storm tracks. Color coding indicates tropical depressions (green), tropical storms (yellow), hurricanes (red), and post-tropical storms (gray).
What ingredients are needed for tropical systems to develop?
Tropical systems form from areas of low pressure that
develop rotation (counterclockwise in the NH and clockwise in the SH) as the
storms’ pressure decreases. For the storm to strengthen, it needs favorable
conditions to cause rising air in the center, which drops the pressure at the
surface. One ingredient is ocean surface temperature of 80 F or higher (27 C)—that
explains why almost no storms develop in the southeastern Pacific or southern
Atlantic, since both are far too cold. Tropical storms and hurricanes are
considered to be “warm core” systems with the air in the center of the storm
staying warm all the way to the top of the circulation. The peak season of
storms in the Atlantic is related to the cycle of ocean temperatures, with the
highest likelihood of storms in the period from mid-August to mid-October. As
ocean temperatures warm, this could mean a shift in hurricane season in the
future.
For spin to develop, you need a force called the Coriolis
force that affects the atmosphere due to the earth’s rotation around its axis.
The Coriolis force is zero at the equator so any areas of low pressure that
form in that area can’t develop the necessary spin to form storms. Another ingredient
is light winds higher up in the atmosphere. This allows the vertical structure
of the storm to develop a strong circulation that ultimately becomes a
hurricane. This becomes important when we talk about the impacts of El Nino and
La Nina on predictions of tropical seasons, since El Nino years have much
stronger jet streams in tropical regions than La Nina or neutral conditions do.
The curvature of the tracks is due to the mid-level winds in
the atmosphere that steer the storms as they go through their life cycles. The
counterclockwise flow of air around ridges of high pressure systems push the
storms along their edges. This often results in a C-shaped pattern as the storm
travels around the western edge of the oceanic high pressure, although the
position and strength of the high pressure will help determine the path each storm
takes and when or if it recurves to the northeast.
Depiction of a hurricane life cycle, from a tropical disturbance (easterly wave off the West coast of Africa) to a fully formed hurricane. Image credit: NOAA/NHC.
Impacts of tropical systems
Some impacts of tropical systems are only found near the
center of the circulation, but others can be found hundreds of miles away, so
even if you are not in the main area that tropical storms affect, you are not
without risk. These storms are not small whirls like tornadoes, but are much
bigger and can take hours to cross a location near the center. If you are close
to the storm’s center, especially if you are on the right side of the storm’s
path, you are likely to experience strong winds, heavy rain, and, if you are
near the coast, the chance of a storm surge coming inland from the ocean.
Farther away, you can experience strong squalls that include small tornadoes,
heavy rains, and gusty winds. These effects are made worse if you live in
mountainous areas where lifted air can cause rapid flooding conditions. Some of
the worst floods in U. S. history are from former hurricanes that traveled over
mountains and dropped incredible amounts of rain, such as Agnes, which caused
the death of 122 people mostly in Pennsylvania, almost exactly 50 years ago.
Even after a storm weakens to a depression or transforms
into an extra-tropical storm, the blob of moisture within the remains of the
storm can be transported by the atmospheric circulation a long ways. There have
been records of typhoons in the Western Pacific Ocean whose watery remains
crossed the ocean and brought heavy rain to the West Coast. Occasionally some
will enter the central United States and drop flooding rain there, too, such as
the remains of Tropical
Storm Erin in 2007.
Hurricane Dennis batters palm trees and floods parts of Naval Air Station (NAS) Key West’s Truman Annex, U.S. Navy photo by Jim Brooks
What gardeners (and everyone else) should know
Preparing a garden for a hurricane is no different than preparing for other types of extreme weather. Survey your property before the season to make sure that no objects that could blow around in high winds damaged are present. If a storm is coming, make sure that your yard is free of garden gnomes, rakes, damaged tree limbs, or other loose objects that could become airborne. Make sure your roofs and gutters can shed heavy rain and have a place on your property to contain rainwater safely. Have supplies of batteries, non-perishable food, and water for people and pets. Put together a plan to recover later by making inventories of your property, including outdoor equipment that you store online. And make a family plan for how to evacuate if you live in an area of flooding and how to contact each other later if you get separated. Cell phones often do not work after strong wind events, so you can’t count on them to bring your family back together quickly after a storm.
What’s next?
I expect to see the Atlantic tropical season start to pick up by mid-August, when the African dust that is currently inhibiting storm formation clears and the ocean temperatures get even warmer. In fact, today’s 5-day outlook map shows an area of possible development in the eastern Atlantic (as of 8-6-2022). This is expected to be another active season, and even though we’ve only had three named storms so far, we will likely see many more storms before the end of November, when the official season ends. In my next blog, we will look at the season so far in more detail.
If you listen closely you can hear the beasties in your garden just a-singin’ that tune. And who can blame them? Warm temperatures and lush green gardens? They enjoy them as much as we do. But sometimes they can be enjoying our landscape a little too much. So now what do you do? Visit the garden chemicals section at your local big box store? Reach for your favorite “natural” or DIY concoction? Ask your neighbor?
Hmmm, maybe not.
What is the best way to deal with the problem? Three letters answer that question. IPM.
Scoutcat logo courtesy of C. Ware, copyright 2000
What is IPM? Integrated Pest Management (IPM) is the management approach you should use to solve pest problems. It can manage all sorts of pests with minimal risks to people, pets, and the environment. IPM’s emphasis is on the management of problems rather than eradication. It focuses on long-term prevention of pests or their damage by managing the ecosystem. IPM is a five step process: 1) correct pest ID, 2) monitoring and assessing pest numbers and damage, 3) pest ID guidelines for when management action is needed, 4) preventing pest problems, and 5) determining correct control measures. Let’s take a look at each one.
#1. Pest ID
Correct ID of the problem-causing critter is the most important aspect of IPM. If you don’t know what you’re dealing with, how can you devise an effective control strategy, if indeed one is needed? So what is a pest? Pests are organisms which damage or interfere with desirable plants or damage structures. Pests also include organisms that can impact human or animal health. Pests may transmit disease or may be just a nuisance. A pest can be a plant (weed), vertebrate (bird, rodent, or other mammal), invertebrate (insect, tick, mite, or snail), nematode, or a pathogen (bacteria, virus, or fungus). A correct ID of the pest must be made before deciding if control is needed. If you aren’t sure you’ve ID’ed it correctly or want a second opinion, take a sample to your local Cooperative Extension Service Office. Note: Be careful about asking for pest ID at a garden center. Employees may not be knowledgable, or your request might be seen as a sales opportunity. And think twice before taking the advice of someone who might try to sell you something.
It never hurts to ask for more input on an ID.
#2. Monitoring and Assessing Pest Numbers and Damage.
You’ve probably heard the saying, “The best fertilizer is the gardener’s shadow.” I’ll make the claim that “The best pest control method is the gardener’s shadow”. For effective monitoring, you need to be out in your garden on a regular basis. Looking, listening, even handling plants, checking under leaves, etc., so you come to know it as well as you know the layout of your living room. You should have a good knowledge of your landscape’s microclimates, soil conditions, the path of sunlight through the year, how seasonal changes affect your garden and a general grasp of the climate. Once you know what’s “normal” for your landscape it’ll be easier to spot any abnormalities.
For example: Your favorite rose always has a few aphids but the population seems to have exploded in the last few days. And why do some of them have wings? Is that slug damage on that hosta? You don’t recall seeing those rusty patches on that hollyhock before. What are the odd black spots on this pomegranate? Hmm…. Always ask yourself how extensive the damage is. Does it threaten the health or life of the plant, or is it largely cosmetic? Do you need more expert advice? Continual monitoring and assessing of what’s going on in your landscape can help you decide if the damage is important or extensive enough to require pest management.
#3. Pest ID Guidelines to Determine if Management Action is Needed
Which one is the pest? They both seem surprised.
Using the biological information of the correctly ID’ed pest will help you decide if you need to deal with the situation. Here are some things to consider when deciding if management is needed. Is the pest short-lived and is only in the garden for a few weeks or even days? Does it only make a seasonal appearance? Is the damage of long duration/the entire growing season, only for a short time and the plant recovers, or is the damage mostly cosmetic? Is it a pathogen? Does it carry a pathogen? Can it cause irreparable harm? Is it an invasive species that can or should be controlled? Does it threaten a needed food garden? Is the damage really that bad?
Knowing the life cycle and feeding habits of your ID’ed pest will help you determine if control is necessary. Use their biology against them. Do your homework.
So you have a plant issue and you’ve correctly ID’ed the pest and the problem. It needs to be dealt with. What’s your next step?
“And you may ask yourself, “How do I work this…”? “Once in a Lifetime“ by the Talking Heads
#4. Preventing Pest Problems
“An ounce of prevention is worth a pound of cure.” applies to landscapes as well our personal health. Ask yourself if the garden problems you’re facing, most of which will be cultural, can be handled with preventative measures. Are you over or under watering? This stresses plants which can attract pests. Is the plant that is under attack in a less than optimal location? Can you move it or change its environment to help it become healthier? Or should you just remove it and let the Japanese beetles eat somewhere else? Are you practicing good garden sanitation, are you cleaning up those camellia leaves and blossoms after they fall, are you turning that compost pile and ensuring it heats properly in order to kill pathogens or pests? If your growing zone allows it, perhaps you could plant your summer squash or tomatoes later and avoid that first rush of squash bugs or hornworms? (Keep in mind that hornworms are larval sphinx moths which are an important bat food source.) Have you tried using row cover to exclude problem insects or other pests? Be sure you’re not causing the problem. A little garden evaluation can do a world of good. The decision you make here will determine the road you take in dealing with your pest issue. You’ve identified the pest, done some sleuthing and have an idea of the scope of the problem in your landscape. Now you have to decide what is the acceptable level of this pest to have in your yard. And as always, “Right Plant, Right Place”.
#5 Determining Correct Control Measures
Start at the base of the pyramid when choosing control measures
After analyzing the situation you’ve determined you need to engage in some form of pest control. But what should you use? Always strive to use the most benign yet specific form of control you can. Use the method which best targets the problem. A combination of control methods usually give the best results. These include biological, cultural, mechanical/physical, and chemical/bio-rational measures. Start at the base of the pyramid (see above image) and work your way upward. Always allow sufficient time for methods to yield results. Pest problems rarely happen overnight. Early intervention is the key to control. See #2 above.
If you are forced to use pesticides always use them as a last resort, not as a first option. Avoid using systemics on plants which are used by pollinators or other beneficial insects. Avoid using broad spectrum pesticides and keep in mind that many pesticides which are approved for “organic” use are more toxic and less selective than “synthetics”. An exception to the “avoid broad spectrum pesticides”: there can be times when a broad spectrum herbicide, such as glyphosate, is needed to kill both monocots and dicots. Use with care and follow label directions.
Always target the specific pest or problem.
To review: Please follow the IPM Five Step Process: 1. Always ID the pest correctly. 2. Get to know your own landscape. Monitor and assess pest numbers and damage to determine if intervention is truly needed. It often isn’t. 3. Use the pest’s life cycle and feeding habits to decide if or when management action is needed. Use their biology against them. 4. Prevent pest problems in the first place. Be sure you’re not part of the issue. “Right Plant, Right Place.” 5. If necessary, determine the correct control measures and always choose the most benign method which will do the job. Keep in mind products labeled “natural” may not be the best or safest option. Avoid DIY concoctions. They’re usually ineffective, harmful and an illegal use of ingredients.
If you live in a place where water falls from the sky during summer this blog is perhaps not so helpful. However, gardeners in much of the western United States will suffer this summer from hot days (sometimes record breaking) and will need to irrigate their gardens and trees in order for them to survive impending drought conditions. The ongoing drought has drained reservoirs and flows of rivers are down or, in some cases, dry entirely. Due to water scarcity, purveyors are restricting water use outside of homes and in some cases curtailing all landscape irrigation. Using water wisely in the landscape has never been more relevant than now. In this blog post we’ll continue to explore saving our gardens from drought and touch on water use, water demand and plant stress.
Good news — Bad news
The good news is that the longest day of the year was last month. That means that the days are ever so gradually getting shorter. As days shorten, plants use less water. Water use is tied directly to photosynthesis and when the lights are out there is no photosynthesis. Shorter days mean less demand for water. The bad news is that we may have record breaking hot days ahead. Plants become susceptible to wilt, sunburn and dieback during very hot weather. The best way to prevent this is to ensure that roots are moist during very hot weather.
The combination of drought and heat caused sunburn to these privet leaves
Mediterranean Climate
It turns out that in Ventura, CA the longest day of the year is one of the historically driest months (least rainfall) and the shortest day occurs in a month with more rain than average. This is a classical Mediterranean climate, the rain falls when we least need it for thirsty plants. Plants may not use all the water that falls in winter but soil is leached of salts and deeper soil layers are filled with water. Large woody plants can utilize this deeper soil water in drier months.
In a Mediterranean climate little rain occurs in the summer months
Stress
What is not obvious is that stress, especially water stress, is not highest on the longest day but occurs and builds later in the summer and fall months. This is because water is slowly depleted from soils over time. Water use is compensated by irrigations during dry months so stress may not build depending on the effective use of irrigation to keep plants hydrated. Plants and gardens that are less reliant on irrigation build stress over time CUMULATIVELY until they are irrigated or rain falls again. So after the spring rains stop, the “stress clock” starts ticking and keeps building until rain or irrigation happens again in the fall or winter. It is no wonder that symptoms of stress such as wilt, sun burnt leaves, leaf fall and plant death occur in late summer when cumulative stress levels overcome plant physiological limits. Late summer often is the time when the hottest days occur and heat stress in addition to drought stress adds to the struggle for garden plants.
Adding stress bars (red) shows how stress builds over time if there is no rainfall or irrigation
Save your plants in the fall from deadly stress
In the late summer or fall months plants are most likely to die of drought induced stress. This can be forestalled by irrigation applied in August which will reset the stress clock to lower levels. Stress won’t return to low wintertime levels because irrigation water is often of less quality than rain water. The salts in the irrigation water raise the osmotic potential of soil water creating another kind of stress. When it rains, these salts are washed from soil and plants are at their lowest stress levels.
Monsoons (see recent blog by Pam Knox) provide arid climates with stress relief when plants growing in hot deserts most need it. Many plants come out of dormancy or germinate only after the onset of summer rains. While monsoonal moisture can be unpredictable usually some rain falls in the desert southwest. In years when the monsoons don’t come or provide only low amounts of water, some trees or other woody plants even cacti, may die from stress.
Monsoons in Portal, AZ, July 2022.
Monitor your plants for stress as long dry periods or hot weather get longer and hotter. Apply water strategically to take off stress. Irrigate deeply by soaking the root ball(s) of the plant(s) you want to save. Established plants are pretty tough and can survive adverse periods, newly planted specimens not so much. They must be irrigated frequently just like they were in the nursery until their roots are will grown into site soils. For those of us living in a Mediterranean or monsoon climate we should wait until the onset of a wet period is near before installing new plants.
It may seem odd to sing the praises of a weird, sometimes gross, looking phenomenon that sometimes freaks gardeners out, but every summer I love educating gardeners about the fascinating lives of slime molds. Here in Nebraska we often get calls about “this weird thing that’s all over my mulch” after a rainy period in the summer and whether or not it will 1) hurt their plants, 2) poison them, or 3) some other horrible outcome they’ve dreamed up. But the fact is, not only are slime molds harmless they’re also quite fascinating. In fact, I’ve often thought if I ever had the right terrarium setup, I’d love to have a pet slime mold. No joke.
What is a slime mold?
Basically speaking, slime molds are a group of eukaryotic organisms similar to amoebae that feed on microorganisms and do some pretty amazing things for simple-celled organisms. They can often be found in soils, forests, especially wetter ones, where they live on the microorganisms that are breaking down fallen logs and detritus on the forest floor. In gardens, you’ll find them in areas with heavy, woody mulches or high organic matter. (They also live in rain gutters if they’re full of leaves and also air conditioner units with poor drainage, FYI.) Most of the calls that we receive at the extension office are from suddenly finding slime mold in woodchip mulch. Usually after a large or extended rain event during the summer, and usually in thickly layered (several inches) mulch.
When food (microorganisms) is abundant, the majority of a slime molds, at least the ones in the “cellular slime mold” category live most of their lifecycle is as a single cell, imperceptible to humans. But when food becomes scarce is when the fun begins. In mulch, this can happen when the weather conditions (wet and hot) favor a slime mold population boom thanks to sexual reproduction and they eat themselves out of house and home. When that happens, the individual cells join together as a single body (one big cell blob with multiple nuclei), forming a visible and for many disconcerting presence in the landscape. Many of them look like actual slime and several look like webbed networks or neural structures.
Slime mold on mulch | Jody Green, UNL Extension @JodyBugsMeUNL
The most fun thing about slime mold, though, and the thing that I love about them is that THEY MOVE! Yep, you heard that right. These single-celled organisms, that stream together to form a single body, can chemically sense the presence of food in the nearby environment and will change shape (together) to move toward the food. And they’ll follow the food wherever it is – on the ground, up on a plant, into the canopy of a tree, etc. Scientists have demonstrated this by having slime molds solve mazes or even create designs, like the Tokyo subway system, in vitro. The trail of slime that it leaves in its path even relays a chemical signal that it uses to “remember” where it has been so it doesn’t backtrack or go the wrong direction.
Several of our concerned callers call because a slime mold has moved up onto one of their plants and they want to know if 1) it will kill their plant and 2) if it is toxic. Neither of which is the case. But most of our calls happen when our most common slime mold in the area moves onto its next phase of life – spore production.
You see, when environmental conditions change or the slime mold finds a good supply of food it is time to settle down for some good old-fashioned asexual reproduction. The shape and texture of the slime mold changes, usually becoming more pronounced and dryer looking as it produces sporangia that produces spores.
Callers often describe what looks like dog vomit in their landscape, and that’s where our common slime mold gets its name – the Dog Vomit Slime Mold (Fuligo septica).
Shortly after this phase, the collective body of the slime mold will dissipate. Spores will turn into new single-celled organisms that will repeat the process over again.
Can it be stopped or controlled?
First of all, why would you want to stop this fascinating phenomenon in your garden? (I’m kidding). Really, there’s nothing you can do as a control and there really isn’t a need to do so. As I stated earlier, slime molds do no harm to plants and aren’t dangerous for people or pets. If you just don’t like the look of it, you can reduce the likelihood of it popping up in your landscape by reducing the thickness of woodchip mulch (don’t let my GP colleague Linda hear me say that) or reduce irrigation if it is occurring outside of larger rain events.
Otherwise, just enjoy your pet! It won’t hang around for long. The visible, fascinating life of a slime mold is fleeting but exciting. Next time you see a slime mold, check it out! And keep an eye on it to see if it moves or if it progresses through its life cycle – maybe you’ll just develop an appreciation for them, too. And I’m not joking about pet slime molds, someone even wrote a guide to dog vomit slime mold pet care!
