tree treatments discussion

[NCTREE]

What about flexible black soaker hose. In circle the root system keeping the hose spaced 3' apart. You have to water more frequent and longer but it seems sufficient.

 

[jefflovstrom]

Treevet, I agree with you that frequent shallow watering does not promote proper root development. The same is true, both for lawns and for trees.

In your best, anti-lawn response, can you honestly say that you have ever seen a tree suffering from drought stress in an irrigated lawn?

Some of my thoughts on the topic:

1. Lawns are invariably over-watered. Watering well for the trees does not over water the lawns, unless you are already watering plants that don't need it.

2. The vast majority of the tree roots is in what, the top 18" of the soil? That is right where the grass is living, too. They both get the same water, although some trees sink their roots fantastic distances for water. All that means is that the trees will get water when the grass has dried up. It doesn't mean that the trees can only get water from deep in the earth.

3. Drip irrigation will create a root system that surrounds the emitters. Unless you infest the ground around a tree, you may be causing the tree to have a rather limited root system dependent upon the irrigation. Unless, of course, you only turn it on when drought comes to town. [Probably at the same time that no-watering ordinances kick-in!]

4. I don't think I have ever seen trees suffering from poor nutrition, poor maintenance related disease, or stunted growth in a well maintained, fertilized, and irrigated yard. WHY do so many arborists promote that good lawn maintenance is bad (or inadequate) for the trees? Show me some pics! Maybe an example or two?

You almost got them, Dude. I was waiting for the part where you would say there is an enviroment in which the landscape includes the trees.
Jeff

 

[treevet]

In your best, anti-lawn response, can you honestly say that you have ever seen a tree suffering from drought stress in an irrigated lawn?

Yes, absolutely. What would be sufficient water for the tree when applied to a lush lawn above the tree root zone suddenly becomes not enough for the tree (and lawn together). Have seen it countless times. You are telling me you have never witnessed a weak or dead tree in a watered lawn??? Have you done research on this?

Let's also acknowledge that lawns are a contrived, artificially created entity (probably the basis for the quote "trees and lawns have different watering cycles").

Some of my thoughts on the topic:

Let's dismiss your conjecture and go to the experts. I could write a volume but a couple of quotes should suffice.

"Trees have woody roots for support and energy reserve storage, non woody roots that absorb water and elements. Most non woody roots are very shallow. In natural forests where there is decaying leaf litter, the nonwoody roots, and especially mycorrhizae, will be abundant in the highly organic top layer of soil. Grass roots will compete with tree roots for water and elements. A common new problem is tree decline in lush lawns that have no weeds." (maybe also from use of broad leaf weed killers and trees are "broad leafed plants...Treevet comment) Pg. 289 Modern Arboriculture, Shigo.

"Mowed grass is an acceptable surface but has many drawbacks. Lawn requires relatively frequent maintenance and invites potential damage to the tree base from mowers and competes with the tree for resources. Its watering cycles are different from trees." page 280 Up By Roots, Urban

"Evaluating the site": Other factors; Other factors to consider include competition from other plants and lawns, ......

Tree roots grow in the top 18 inches of soil and compete directly with lawns and other plants for available nutrients."page 30, Plant Health Care for Woody Ornamentals, A Professional Guide to Preventing and Managing Environmental Stresses and Pests. ISA

Let's not forget that nutrients are delivered by water and both are necessary to survival. In times of abundance this competition may not be an issue but in difficult times this competition may put a tree in a compromised state (treevet's comment).

2. The vast majority of the tree roots is in what, the top 18" of the soil? That is right where the grass is living, too. They both get the same water, All that means is that the trees will get water when the grass has dried up

.

I do not understand that thought.



4.

I don't think I have ever seen trees suffering from poor nutrition, poor maintenance related disease, or stunted growth in a well maintained, fertilized, and irrigated yard. WHY do so many arborists promote that good lawn maintenance is bad (or inadequate) for the trees? Show me some pics! Maybe an example or two?

You cannot be asking me to show you a tree that looks bad in a yard with a healthy lawn can you?

 

[pdqdl]

TV, we aren't that far apart in our understanding of how things work, it's just that you are a dedicated "tree-first" kind of guy, and I try to look at everything equally. We have beat this topic up before, so it's not worth making a big fight over. My comments in burgundy. Some parts trimmed for brevity.

Yes, absolutely. What would be sufficient water for the tree when applied to a lush lawn above the tree root zone suddenly becomes not enough for the tree (and lawn together). Nope. I have never seen leaf scorch in an irrigated yard. Have seen it countless times. You are telling me you have never witnessed a weak or dead tree in a watered lawn??? Sure. Lots of dead trees in irrigated yards. It's part of the cycle of life. However, I must say that the number of dead trees that I see in irrigated lawns is absoutely dwarfed by the number of dead trees that I see in non-irrigated areas. Have you done research on this? On this specific topic? I don't think it exists. A while back I posted some research that demonstrated that the microenvironment above turf, both irrigated and non-irrigated, was more conducive to shrubs and low growing trees than either mulch or bare dirt. Curiously, bare dirt outperformed the mulch in that respect.

Let's also acknowledge that lawns are a contrived, artificially created entity (probably the basis for the quote "trees and lawns have different watering cycles"). Yes, without a doubt. So is the nursery that we grow our landscape trees in, as well as every other aspect of urban culture.

"... A common new problem is tree decline in lush lawns that have no weeds." (maybe also from use of broad leaf weed killers and trees are "broad leafed plants...Treevet comment) I agree completely. In fact, that is the first place that I would look for a solution. This is why I seldom spray broadleaf weed control as a blanket application in the landscape. Sadly, I don't agree that the lawn is the culprit. The biggest lawn problem that I see nearly every single day is well established, fertilized, irrigated lawns that are bare ground beneath the big, beautiful, perfectly healthy trees. When it comes to competing with the trees, the lawn looses every time.

"Mowed grass is an acceptable surface but has ... Its watering cycles are different from trees." In a completely natural setting, they both get the same water, with survival of the fittest. In my experience, that is always the trees. Gotta disagree with that one.

Let's not forget that nutrients are delivered by water and both are necessary to survival. In times of abundance this competition may not be an issue but in difficult times this competition may put a tree in a compromised state (treevet's comment). Well...ok. Any tree on the edge of demise will suffer from competition. Why is the tree in decline? The vast preponderance of trees that decline in this country do so completely without any intereference from lawns or mankind. Just look on Google Earth and any forest.

I do not understand that thought. My point is that "deep watering" and "deep fertilization" are not beneficial to the trees to the exclusion of the turfgrass. They are competing in the same root zone. Shucks, buffalograss has been shown to root 19' deep, and I don't know of any turfgrass that doesn't root several feet.

You cannot be asking me to show you a tree that looks bad in a yard with a healthy lawn can you? Well...no. That would be too easy. I would sure like you to show me a statistical compilation of where there are more tree problems: irrigated, pampered yards, or just plain old lawn mowed once every two weeks.

This is a good dialogue so far. I am genuinely interested in your opinion, and am willing to convert if you can convince me. Unfortunately, right now I see things a little differently.

 

[treevet]

It is impossible to direct quote you when you reply like you did without a lot of work but it is easy to see that you are a lawn advocate likely in preference over trees. You likely would advocate having lawn right up to the buttress flare.

But it is commonly accepted contemporary researched knowledge that a mulched bed over the root zone is preferable to lush lawn. This is why mulch beds are NOW put under new trees and groves and most often chosen to be formed under established trees. You choose to ignore commonly accepted researched knowledge despite 3 of the myriad quotes I could have provided to challenge your position.

When I say lawns are a contrived artificial entity you simply compare the situation with trees that have been planted. But many times homes are built with trees already in the landscape or woods. Homes are never built in a lush weed free lawn area that pre existed. Nor could the lawn exist or even survive without being catered to with much money poured on it and effort. Trees could.

You state that shrubs and LOW GROWING trees have been proven to exist better in irrigated turf than bare dirt or mulch (unirrigated?). I doubt that but we are discussing LARGE growing trees (at least I am).

You state that when conditions are extreme that trees come out the better in competition than lawns do. I doubt that. Can you cite research to substantiate this? Sometimes it takes years to show the damage done to trees in this situation.

When I state that when times are most difficult (drought) that this is the time (like we are having in my area now) that the grass becomes a huge deficit in the struggle for survival of trees and their ability to defend themselves from insect and disease attack (if a lush lawn is over the root system).

You chose to distort my thought as appearing to mean that the tree is near death and ofcourse it is not the lawn that is at fault.

And finally you want me to provide you with researched data showing that irrigated lawns are more difficult on trees than a plain old lawn that is mowed.

My premise is that mulched (not any lawn) surfaces capturing any precipation whether artificial or natural is way better than any lawn especially a lush, chemical laden, contrived water sucking carpet.

I think we have beat this to death also and do not plan to respond unless you post in a fashion that can be quoted. But you have to agree with a simple fact.....

A mulched area under a tree will capture water (the op subject) for the tree's fibrous root system better than if it has a lush lawn growing over it?

Just give me an answer to the simple last question pdqdl, before you address the rest of the post please.

 

[Garden Of Eden]

TV & PDQDL, I have nothing to add to this, other than you both have a ton of knowledge about this it would appear, and I'm impressed.

Thanks for the info guys.

Jeff

 

[jefflovstrom]

opcorn:
Jeff

 

[dingeryote]

Not to butt into the very informative debate.

But has anyone tinkered with sub-soil trickle to get Partially UNDER the lawns root mat?
Granted it wouldn't be 100% delivery, and loss to the competing lawn would be there, but a reduced amount. Or would the dadgum grass overwhelm things quickly?

Done properly, with a timer and a Mazaei injection system inline, water flow could be controlled as needed, and nutrients added as needed during stress.
That, and it's not apparent to the prying eyes of busybody neighbors nor waternazis.

The growth near the emitters issue is understood, but if it's used only during stress periods, and emitters are spaced every 12-24" how badly would the growth be concentrated?

Additionally, I wonder if trickle added to trench mulching would have any benefit? It would require some interesting design, but 18mm buried trickle line isn't awfull expensive nor difficult to work with.

Just tossing this out there, because I am pondering subsoil irrigation in very sandy soil, and looking towards subsoil mulching for another purpose that has some paralells.

Thanks!

Staysafe!
Dingeryote

 

[treevet]

Sounds like a viable option esp if not dealing with acres of trees.

 

[dingeryote]

Sounds like a viable option esp if not dealing with acres of trees.

Thanks!
I wondered.

Possibly, if it can be filtered enough not to clog emitters, good old compost "Tea" could be used to get a shot of chow to the fibrous roots, untill I can get enough organic matter tilled in, and the trenched mulch starts breaking down.

I'm dealing with several thousand bushes in rows, and got to thinking about trees and lawns, while mulling over weeds in new plantings.
I can cheat a bit with cultivation, ya can't on a lawn.

Stay safe!
Dingeryote

 

[pdqdl]

...

A mulched area under a tree will capture water (the op subject) for the tree's fibrous root system better than if it has a lush lawn growing over it?

Just give me an answer to the simple last question pdqdl, before you address the rest of the post please.

No, I won't agree that mulch captures more water. I will conclude, however, that it does a much better job of retaining water.

Thick mulch usually forms fungal mycelium mats that are somewhat impervious to water. The same thing occurs sometimes in lawn areas; when this occurs they are called "local dry spots". The water has a greater tendency to run off of these areas. Obviously, mulch types and condition, and how often it is disturbed will play critical roles in how well it absorbs water. Similar considerations are required for lawn/soil conditions as well.

Water use for this comparison should be broken into 3 different aspects: absorption vs runoff rate, total capacity, and water retention rate. I have already given my comments on absorption (in response to your question), but I thought I should add something on the other two topics.

Total water holding capacity: Rich topsoil has a greater capacity to hold water than the average shredded hardwood mulch, in that it has much greater humus content, and it generally will have a much smaller average particle size. The surface tension of water dictates that more water will be retained in the material with the smallest particle size. If you don't believe me, take a bucket filled with topsoil and one with mulch; weigh each bucket. Add water until they are totally saturated. Pour off the excess water, then weigh them again. You will find that the topsoil retains more water than much every time.

So; does mulch hold more water than the same amount of topsoil filled with turf? No. Given that mulch is generally piled on top of the topsoil, and does not usually displace any topsoil, this is almost a moot point. The addition of mulch on top of topsoil will certainly retain more water than topsoil/lawn alone.

Water retention rate: In the study that I obliquely referred to previously, mulch was found to have the least favorable micro-environment above it than either bare dirt or lawn. This is because it reflects heat back up to the plants above it rather than absorbing the heat, and it also transpires less moisture back up into the air above it. Woody plants that were located in the fairly shallow area of higher humidity and lower reflected heat performed better in these areas over lawn than they did over much. Sadly, the zone of higher humidity and lower heat does not even come close to helping out your average shade tree.

The very traits that causes mulch to be less desirable in the 6' tall microenvironment above it, are what also enable it to outperform lawn surfaces in this respect: water retention. Because mulch reflects heat better than either bare dirt or lawn, and it does not transpire moisture anywhere near as well as lawn, I think it is pretty safe to say that the soil beneath a nice thick mulch layer will always have more moisture than the lawn immediately adjacent.


No, TV, I'm not an advocate of lawns over trees. Nature is filled with a magnificent array of plants, and I like them all. I am as equally impressed with the beauty of a well formed oak as I am by the best of lawns. When I go for a tour across the country, I cannot say that I enjoy driving through the open prairies any more or less than in the forests or the mountains. While the desert and arid regions are interesting, I distinctly don't like them as well as where either grass or trees thrive. One of my favorite things to see is a meadow infested with dandelions, yet I make a good amount of my income from wiping them out.

Here is one of my favorite pics:

Yes. I mulch my trees, and I think it is both beneficial to the trees, and it makes the yards easier to mow, too. I just have a hard time understanding why so many people advocate wiping out the lawn beneath all the trees.

Trees are the apex predators of the vegetable world. It's like saying that the fleas and the tapeworms are killing off all the lions, and we should take preventative steps immediately to protect those poor endangered lions. All the while, we seem to be overlooking the more important considerations (for the purpose of this analogy) of whether the lions have anything to eat, and whether they are being killed off by hunters or other predators.

 

[pdqdl]

When I say lawns are a contrived artificial entity you simply compare the situation with trees that have been planted. But many times homes are built with trees already in the landscape or woods. Homes are never built in a lush weed free lawn area that pre existed. Nor could the lawn exist or even survive without being catered to with much money poured on it and effort. Trees could.

No, I agreed with you!

I also pointed out the urban culture is artificial with respect to trees, too. I am not a forester, and I am not generally concerned with the health of forest trees. I am an arborist, landscaper, lawn mower, and general contractor in the big city. My concerns involve meeting my customers desires, which means giving them a landscape that looks like what they want it to.

I try to keep everything in balance.

 

[pdqdl]

...

You state that shrubs and LOW GROWING trees have been proven to exist better in irrigated turf than bare dirt or mulch (unirrigated?). I doubt that but we are discussing LARGE growing trees (at least I am). ...

No, I didn't.

I stated "A while back I posted some research that demonstrated that the microenvironment above turf, both irrigated and non-irrigated, was more conducive to shrubs and low growing trees than either mulch or bare dirt."

This study formed no conclusions at all about "proven to exist better...". It only commented on certain conditions. I drew no further conclusions, and I think that it is erroneous to make more conclusions than the authors did.

 

[pdqdl]

...

You state that when conditions are extreme that trees come out the better in competition than lawns do. I doubt that.
...

No, I did not say that at any time.

I only stated the the lawns always loose to competition with trees. Just pick your best customer with the very best trees: look at the lawn beneath (or near) those same trees.

Then pick your customer with the very best lawn. Are all their trees dying off from turf related issues?

******************************************************
I should probably rescind my statement about grasses always loosing to trees.

The reason that the prairies predominate in the midwest USA is that they catch on fire and kill off all the trees. Grasses do recover and survive fire much better than trees do, and they generally survive in lower precipitation areas because of their ability to go dormant. Trees can't go totally dried out and dormant like grasses, so they loose in that ecological niche.

Conversely, where they don't get burned up by prairie fires, the native trees generally stay green all summer, while the lawns in those areas often go dormant and brown. Why? Trees root deeper, and have more moisture available to draw upon. Obviously, annual rainfall is very important to this argument.

There is a cave in southern Missouri that has trees roots coming into the ceiling several hundred feet below the surface.

 

[pdqdl]

When I state that when times are most difficult (drought) that this is the time (like we are having in my area now) that the grass becomes a huge deficit in the struggle for survival of trees and their ability to defend themselves from insect and disease attack (if a lush lawn is over the root system).

I can't argue with that. I don't know that grass is a huge deficit, but any competition for a plant that is struggling will be a problem. It is certainly easier to rebuild a lawn than it is to restore a dead tree, so I would support any maintenance option that supported the trees, if I could only choose between keeping the lawn or keeping the trees.

On the other hand, isn't it easier to just provide what the tree needs (water) than it is to kill off the lawn?

 

[treeclimber101]

I've seen this method work to some extent in small back yards.

I tell people to soak the basal area of the tree, I have started "dishing out" basal areas so water will be detained and perk through.

Then there is Wulkie's study with his large I.D. hoses where he watered Chicago park trees with a drip-line flood. I've taken to calling it "perk irrigation".

Another method I have seen work is to put a kiddie pool out under the tree, knock holes in the bottom so that it will drain slowly. I've told people to do this when there are watering restrictions in a region.

A few years ago, a local company was doing macro-fusion w/ highly dilute fert to get water into specimen trees.

Or just use gator bags , sounds like the same process ...

 

[pdqdl]

And finally you want me to provide you with researched data showing that irrigated lawns are more difficult on trees than a plain old lawn that is mowed.

Yes. Unless I misunderstand your arguments, you stated that lawn sprinklers were inadequate and unhealthy for trees.

I asked:
In your best, anti-lawn response, can you honestly say that you have ever seen a tree suffering from drought stress in an irrigated lawn?

You responded:
Yes, absolutely. What would be sufficient water for the tree when applied to a lush lawn above the tree root zone suddenly becomes not enough for the tree (and lawn together).

Why not just set the irrigation settings for the health of the trees? The lawn will do fine on what is plenty for the tree. On whatever schedule might be selected.

 

[pdqdl]

...
My premise is that mulched (not any lawn) surfaces capturing any precipation whether artificial or natural is way better than any lawn especially a lush, chemical laden, contrived water sucking carpet.

...

Well, almost no argument from me. Mulch doesn't capture more water, but it does hold it better.

Is mulch better for the tree than lawn? Certainly!
That is like asking a lion if it prefers to have fleas!

How many of your customers are willing to sacrifice their lawn in favor of getting the ultimate in tree health? Not very many of mine will! I believe in balance and moderation...in everything!

By the way: lawn does suck up the water; both into the soil when if falls, and out of the soil when it is hot. When it comes to water transpiration rates per acre of ground, trees beat the snot out of lawn for sucking water out of the soil.

 

[treeclimber101]

Well, almost no argument from me. Mulch doesn't capture more water, but it does hold it better.

Is mulch better for the tree than lawn? Certainly!
That is like asking a lion if it prefers to have fleas!

How many of your customers are willing to sacrifice their lawn in favor of getting the ultimate in tree health? Not very many of mine will! I believe in balance and moderation...in everything!

By the way: lawn does suck up the water; both into the soil when if falls, and out of the soil when it is hot. When it comes to water transpiration rates per acre of ground, trees beat the snot out of lawn for sucking water out of the soil.

ACTUALLY turf drinks 95% of the water in the first 8inches if soil so mulch isn't important its essential to the overall health of the tree , my issue with mulch is overmulching can cause what I call a water slide away from the tree where very little water even gets to the roots , its equally important to remove as much OLD mulch as you install , and aerating around the dripline ...

 

[treevet]

No, I won't agree that mulch captures more water. I will conclude, however, that it does a much better job of retaining water.

My statement was that it captures more water for the tree (by retaining not absorbing) just as a road grate captures water from pavement.

If you have to have lush green lawns.....make as big a mulch ring around every tree that the client can stand imo. Ofcourse the mulch ring should be properly done without hardpan beneath it or piled too high and ideally composted mulch that will not support disease of the parent material and protected from being washed away if nec.

pdqdl.....if you take your cursor and place it to the right of the sentence or paragraph you want to quote.......then drag it with the mouse to the left (it will high lite your intended quote).....then go above the post box and left click on the little square box that has a point on the bottom and looks like a quote in a cartoon.

This will give you a quote of the part of someones post you want to seperate and you can type below it responding to it.