I’m in Grand Rapids this week attending the Michigan Nursery and Landscape Association/Michigan Turf Foundation Great Lakes Trade EXPO. The topic for my talk today was Landscape Tree Fertilization. That might not sound like a subject that would generate controversy, but as with most things, there are camps emerging. There is a rising chorus of folks that suggest that landscape trees should not be fertilized with nitrogen. There are a couple of lines of evidence that bolster this point of view.
Category: What About the Trees
Friday puzzle solved!
Great discussion over the weekend, with some very astute observations. If you looked at the brown needles under the tree in Friday’s picture, you may have noticed that some of them weren’t needles:
Not only was this tree planted too deeply, as several of you pointed out, but the burlap and twine were left intact. It appears the nylon twine has already started to girdle the trunk, based on the trunk swelling just above where the twine is wrapped.… Continue reading this article “Friday puzzle solved!”
Friday fun!
It’s the holidays, but this pine tree is feeling anything but merry. It was installed about a year ago. While the upper foliage looks lush and green, the lower branches have no new needles and in fact the current needles are dropping:
This is a two part question:
1) What might be directly responsible for the needle decline on the lower branches? (Hint: this is caused by the plant itself.)
2) What might be the underlying stress causing the needle decline? … Continue reading this article “Friday fun!”
Inspecting nursery plants, part IV
(Note: this is a really LONG post. Not in text – but in photos! Sorry for all the scrolling.)
I don’t know about you, but after spending three weeks on my hands and knees looking for trunk rots, surface roots, and suckers, I’m ready to become bipedal again. So today let’s look at trunks – and what shouldn’t be missing on them.
Many young trees have numerous short branches along their trunk, as shown in the photo below:
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Unfortunately, many nurseries and gardeners think this looks scruffy, and respond by pruning these branches off, leaving a tree such as the one in this picture:
Personally, I think these trees look like lollipops, but aesthetics aside, this type of pruning can inadvertently damage young trees. … Continue reading this article “Inspecting nursery plants, part IV”
Inspecting nursery plants, part lll
By now you’re probably ready to stand up, brush off your pants, and stretch your back after crawling around looking for surface roots and root crowns. Not so fast! There’s one more thing to look for – and to avoid.
Take a look at these two photos:
You can easily see the suckers at the base of these trees. Whether or not they are actually suckers (coming from the roots) or watersprouts (coming from the base of the trunk) doesn’t matter. … Continue reading this article “Inspecting nursery plants, part lll”
Advice Requested!
Greetings, all!
I am not a tree-care expert, having invested most of my mental capital into herbaceous plant stuff. But I know enough to be dangerous: spiraling/strangling roots and narrow crotch angles are bad news. But at what point do they become “unfixable”? So I’m asking my illustrious colleagues and diligent readers (a.k.a “all y’all) for advice.
We have a lovely specimen in our campus Horticulture Garden…Acer ‘White Tigress’ – a hybrid between A. davidii and A.… Continue reading this article “Advice Requested!”
Inspecting nursery plants, part ll
Well, I’m recovering from this simply horrific chest cold or whatever it is and feeling brain function returning. The last time we were at our virtual nursery, we were looking for root flare and inspecting the trunk for damage from improper bagging. Since we’re already down on our hands and knees, let’s consider roots. In general, you really don’t want to SEE roots, except where they meet the trunk (the root flare). The presence of coyly crossed “knees” in this photo is a clear indicator of a plant that wasn’t potted up quickly enough:
Likewise, while the fused, circling woody root mass in this next photo might be aesthetically interesting, it sure doesn’t make a functional root system:
It’s pretty easy to avoid these types of plants, because you can see the root problems before purchasing. … Continue reading this article “Inspecting nursery plants, part ll”
The World According to Chub
Following up on Holly’s theme of “I can’t believe I get paid to do this”, last Wednesday I participated in a walk-through and inspection of the Justin ‘Chub’ Harper Collection of Dwarf and Rare conifers at MSU’s Hidden Lake Gardens in south central Michigan. The Harper collection is widely regarded as one of the premier collections of rare and unusual conifers in the world.
Harper Conifer Collection with fall color background. Photo: Jack Wikle.
A little background: Chub Harper was the former grounds supervisor for John Deere’s world headquarters in Moline, IL, an avid plant collector, and a founding member of the American Conifer Society (ACS). … Continue reading this article “The World According to Chub”
I see the light!
Here’s the follow up picture from Friday’s puzzler:
As you can see, there’s a street light near the lower half of the maple. (I cleverly hid it behind the utility pole in the first photo.) The green part of the tree never received the message that days were getting shorter, since the street light is bright enough to interrupt the dark period necessary to initiate dormancy.
This is one of my favorite phenomena unique to urban environments. … Continue reading this article “I see the light!”
What Makes Growers Change?
Over the last few weeks I’ve said a lot of complimentary things about the Minnesota Nursery Industry and how they’re careful to avoid situations where trees are planted too deeply. What I haven’t mentioned is that there is a reason for this. During the 1980s and early ’90s trees were usually planted deeply with lots of soil over the uppermost roots. It was just common practice. Unfortunately this practice led to roots growing across the trees stems and, when those roots cross the stem, the roots always win (as you saw in Linda’s quiz last week)! … Continue reading this article “What Makes Growers Change?”