Category: Diversions

Short tree syndrome solved!

Good answers from Kenny S., Jimbo, Joe Schalk and Diana!  You were all skirting about the phenomenon of thigmomorphogenesis – or touch-induced change (also discussed in Jeff’s post of January 7.  The tests in the GP’s class are cumulative!).  In this case, the touch is wind.  Edge trees (or corn stalks) are more exposed and receive more wind, resulting in stunted heights and increased trunk diameter (you can’t see this last characteristic in the Friday photo).  Trees in the middle of the stand aren’t exposed to wind buffeting and put their resources into increased height. Similar stunting and thickening can be seen in urban plantings along the edges of sidewalks or anywhere people or animals routinely walk.

I spent my grade school years in a 1950’s housing development that had been Douglas fir (Pseudotsuga menziesii) forest.  The developers left many of the trees standing, and our backyard was full of tall, skinny and isolated Douglas firs.  When the Columbus Day storm (an extratropical cyclone, of all things) hit the Pacific NW in 1962, seven of these trees came down (none hit our house, fortunately).

Now of course a cyclone will take down many trees, regardless of their location…but this continued practice of leaving trees standing alone during development often results in blowdown or breakage of these now unprotected trees. 

Green mystery disk identified!

Initially I was disappointed that no one answered the question…then Paul W. emailed to say that the post wasn’t accepting comments.  We’re not sure why that happened, but Paul and perhaps many of you knew this was part of the flower of Sarracenia flava – the yellow pitcher plant:

I think this is a stunning flower whose floral structure promotes cross-pollination.  Insects crawl in between the long yellow petals and the green "umbrella" to enter the flower and reach the pollen:

Before they reach the anthers, however, their backs rub up against the stigma, which are five tiny points at the "spokes" of the umbrella.  Pollen already on their backs will be transferred to the stigma before new pollen is gathered, so that the chances of selfing are reduced:

So thanks, Paul, for being so persistant that you emailed me to supply the answer and alert me to the comment fail!

Friday puzzle untangled

A few of you bravely hazarded guesses about this plant, and while it is a contorted specimen, it’s actually Ulmus glabra ‘Camperdownii’, otherwise known as Camperdown elm.  Here’s a photo of a lovely example at Marymoor Park near Seattle:

As plant geeks already know, this odd tree was propagated from a mutant branch discovered on the Earl of Camperdown’s estate in Scotland in the 1800s.  All Camperdown elms are grown from cuttings originating from this single tree grafted onto a Ulmus spp. rootstock which supplies the straight trunk.

Though these trees don’t get terribly tall, they can become quite broad and need space for their tiers of foliage.  Like other contorted trees, the branches of old Camperdown elms can meet and fuse, as you can see in the photo from Friday.  And while the tree produces scads of seeds (that’s what you see in the photo above – not leaves!), they are sterile. 

A Dangerous Game

Every once in awhile I become infatuated with some idea and can’t stop for looking for information on it.  It usually starts when I want to find a good quote for a particular article or column that I’m writing and then ends up swallowing two or three days.  Well, it happened to me again yesterday and spilled over into today.  I’m currently finishing up a project with an old friend of mine from college who happens to be a political science professor at the University of North Carolina Charlotte.  We’re looking at certain environmental issues and the stances taken on them by both the left and the right.  Anyway, I wanted to make a point about biotechnology — that point being that when we graft two plants together we often get different chemicals in the plant which we grafted onto the rootstock than we would get if the plant were growing on its own roots.  This is because many chemicals can be translocated from the roots to the leaves or even the fruit.  Anyway, I quickly found a number of nice scientific articles to back up my statement, but I also found some other fascinating information about, of all things, tomatoes.  There are many plants related to tomatoes that tomatoes can be grafted onto.  For example, every spring our plant propagation class grafts potato roots to a tomato top.  Tomatoes can also be grafted onto eggplant (which is actually very useful because eggplant roots are very resistant to flooding unlike tomato roots).

While the above examples are interesting, they’re also relatively common knowledge among horticulturists.  Here’s the part that’s not common knowledge (or perhaps I should say here’s the part that I didn’t know about — I’ve been known to be ignorant of things that other people consider common knowledge before).  Tomatoes can be grafted onto tobacco, and, if they are, they will have nicotine translocated to their fruit — not a lot mind you.  Most of the nicotine ends up in the leaves and stems of the tomato plant, but still, why couldn’t a nicotine-laden tomato be developed which could help smokers kick the habit — in a semi-healthy kind of way?

I also found that tomatoes could be grafted onto jimson weed.  Big mistake there.  Jimson weed develops some pretty nasty alkaloids, and they end up in the tomato fruit.  So, if you eat the fruit, your done for.  In fact, I found an instance where 5 people were killed because they ate tomatoes grafted onto jimson roots.  I am now curious about what happens if you graft tomato onto deadly nightshade — but not curious enough to actually try it.

Friday geography answer

As several of our astute readers knew, the photo from Friday was taken on the west coast of the Salton Sea in California.  Specifically, it’s at Salton Sea Beach, a nearly deserted region that I managed to make more picturesque through careful photography.  Here’s another picture of the same beach:

There were few plants at Salton Sea Beach – a palm tree here and there – and only a few waterfowl like these pelicans:

The Salton Sea is really the Salton Sink – it’s a low area that has occasionally and naturally filled with water.  Given the high rate of evaporation in the region, the lakebed became highly saline over the centuries.

So what does this all have to do with a gardening website?  Well, the reason the Sea exists today is because of natural flooding combined with agricultural development.  Initially the Sea was seen as a boon to tourism, so spots like Salton Sea Beach and Salton City (near curiously named Squeaky Springs) became tourist destinations.  But as agricultural runoff began to change the nature of the Sea, fish populations failed and so did the tourism industry.

You can see the algal bloom where runoff meets the sea (check out this Google map here).  These desert valleys have been used for conventional agricultural production for many decades, and the results are seen in a sea full of fertilizers and pesticides.

In any case, a visit to the Salton Sea is both fascinating and depressing.  It’s well worth the effort.

Friday geography quiz!

Like last week’s, today’s quiz is a little different.  (I haven’t forgotten about last week’s question – just haven’t gotten a good answer yet!  Never fear!)  In any case, you know I spent some time in Palm Desert CA last week.  On one of our day trips, I took the following picture (we are looking east):

So here’s the question:  where are we?  (It was a day trip, so not terribly far from Palm Desert.)  You can ask questions that I may or may not answer.  Monday’s answer will tell you lots more about this “accidental” landscape!

Oh, Deer…

More from our Ornamental Plant Production class tour across the state.  One of our stops was James River Nurseries, Inc.  Owner Mike Hildebrand has a built a unique and diverse business – they not only grow but do landscape design-build-install, all in the huge market of central and northern Virginia and beyond.

Here’s some arborvitae that spent the past few weeks at one of their job sites north of Richmond, waiting to be planting.  They’re now back at the nursery.  I was going to make this a quiz, but it’s unfortunately just too obvious.

deer nibbles

Wow. Poor things never even made it into the ground.