Pre construction Fertilizing

[rfwoodvt]

Hey All!

Just landed a gig protecting some red maples during construction. Theyv'e given enough lead time to allow for proper preparation of the trees before the heavy equip hackers show up.

Plan is to establish root protection zones, mulch to reduce compaction, aerate, root prune outside the RPZ, clean up the canopy and, after soil analysis, fertilize as necessary.

Here are my questions:

a) any specifics I should consider with the fertilizers?

b) I'm planning on aerating using 2" x 18" cores OR radial trenching. What are the pros and cons of each?

ThanX!

 

[Guy Meilleur]

Originally posted by rfwoodvt
Plan is to establish root protection zones, mulch to reduce compaction,
Good. 6-12" COARSE mulch where traffic will be.
aerate, Why? Is soil presently that compacted? What is the bulk density?
root prune outside the RPZ,
Why? for curb and gutter or trench or footing? No need to root prune if roots will not be cut anyway. Best to mulch well beyond dripline and RPZ fence.
clean up the canopy
Good.
after soil analysis, fertilize as necessary.

b) I'm planning on aerating using 2" x 18" cores OR radial trenching. What are the pros and cons of each?

Core aeration cuts roots. that is a bad thing.
Best to spend $35. on the book Trees and Development. the authors know their stuff, us yahoos are, well, yahoos.

 

[murphy4trees]

What does cleaning up the canopy mean, and why is it good???

Good for the people who are looking at the tree or good for the tree?

Pruning is wounding. I was taught to let the tree make its own decisions about what to lose after construction damage... Seems like that should hold true for before construction damage too.

 

[NYCHA FORESTER]

Air Spade (radial trench), if soil is already compacted.

Mulch (6" is plenty unless material and equipment will be stored with-in the CRZ) and add some N. (when you ask for 6" mulch you generaly get 4")

Dead wood prune only

Cambistat

Try and use a semi-permanent fence do demarkate the CRZ. Flimsy snow fence will only keep the "honest" construction workers out. The first hot day your gonna see atleast a half dozen cars parked beneath it.

 

[Kneejerk Bombas]

Originally posted by NYCHA FORESTER
Mulch (6" is plenty unless material and equipment will be stored with-in the CRZ) and add some N.

Six inches of mulch is almost a lethal dose, why would you do that to a tree?
How about some compost and an inch or two of mulch.
Don't forget to check rainfall and add more water only as needed. Don't overwater.

 

[rumination]

Mike,
Why is six inches of mulch a lethal dose? I had never thought about a tree ODing on mulch before, but I suppose even too much of a good thing can be bad. I just never thought that six inches would be too much, as long as you keep the root crown exposed. Also, wouldn't the appropriate amount of mulch/compost be at least partly determined by the soil type/condition and the climate?

 

[Kneejerk Bombas]

Soil oxygen is the main problem. Roots need oxygen, above around 8%.
Chips with leaves can become "sour" and give off poison gas too.
There can also be problems with root rots from constant moisture.

 

[jimmyq]

If core aerating, consider adding mycorhizzae to the rootzone after root pruning, watch the fertilizer levels if adding Myco though, my info is that high salts can harm.

 

[M.D. Vaden]

Pruning is not wounding - it's pruning.

I've been taught not to let trees make their own decisions in a populated environment.

Trees have no mind by which to guide their growth. Whereas a skilled pruner can select leaders to shift and manipulate a conopy for increased preservation of trees.

To let the trees to themselves is the extremists method of causing chaos and conflict between trees and people.

That's what a forest is for - to do it's own thing away from urban development.

SEE THIS PLUM - See all that included bark? That was a tree left to make it's own decisions. (THIS IS IN REFERENCE TO THE POST ABOVE BY MURPHY FOR TREES)

 

[jimmyq]

did the included bark instigate or aggravate a failure Mario? It looks like it was cut down then analyzed. I do tend to agree with you about the mind thing. A tree may survive with "poor" growth pattern or shape but it may do better with a bit of guidance from folk like us.

 

[Kneejerk Bombas]

We all agree that some structural problems can be solved with prunning, the question is, should this prunning be done just before the loss of much of the trees root system?
I say no.
Unless the limbs are hazardous, the tree will survive better if it keeps every leaf it can. It will want the food those leaves produce when it comes time to compartmentalize all those root injuries and start replacing those lost roots.

 

[Guy Meilleur]

Originally posted by murphy4trees
What does cleaning up the canopy mean, and why is it good???Good for the people who are looking at the tree or good for the tree? Both. From ANSI 4.10: "cleaning: selective pruning to remove...dead diseased or broken branches." what good does it do for the tree to leave these?
Murph and Mike, read the darn book so we all know what "clean" means, OK?.
I was taught to let the tree make its own decisions about what to lose after construction damage...
This is good.
Seems like that should hold true for before construction damage too.

This is not good. Proactive cleaning (and whatever thinning and reduction cuts are *necessary* to accommodate future use of the area) allows the wound response to begin asap.

I agree with NYCHA on cambistat use--a no-brainer. I also agree w mike about dangers of overmulching--that's why I said COARSE. And remember this layer is temporary--whatever is undesirable later can be removed. It's better to lower O2 short-term than to compact long-term. N will solve many of the aaerobic problems you talk about, but coarse is the key.

How many roots will be lost? Saving leaves is a consideration, but not the only one. Cambistat use can lessen concerns over root/shoot balance.

Buy Trees & Development from ISA if you want to do this work.