How much water will a tree pull from the ground in a day

[rfwoodvt]

Hey all!

I've got a customer who is planning on selling their home and they have a very high water table in the neighborhood.

They are looking for some formula or rule of thumb they can use to estimate how much water their trees remove from the ground each day.

This doesn't need to be exact but an approximation to give the new home buyers a chance to understand how important it is to keep these trees.

It is a given that trees can pull a lot of water from the ground, but just how much is the question.

So, can anyone out there help us figure this one out?

 

[Dan R Porter]

I have done no research on this, so i will be impressed if someone has an equation for it. I mean with species, size, site, health/vigor, an approximation is unlikely. Even time of year can affect transpiration. Some birches are known to transpire 1000's, and i mean in the high 1000's, daily, where some trees may be little to none. I will be watching to see what some replies will be. I think a auto-mated sump pump and/or a french drain would be the species I would choose for a wet site, sure some trees will thrive there, but to keep your feet dry, those two species are probalbly the best.

TO justify not removing the tree there are LOTS of things you could tag on like it is a windbreak, shade tree, wildlife home, higher property values (they always widen eye when i say that one) try www.TreesAreGood.com for more. There are MANY

 

[Manco]

I've actually talked to some old-timers that always warned against cutting any large trees where an underground spring emerged. They said the roots draw the water up. Their case being to keep the spring, not dissipate water.

 

[frashdog]

I use wood chips in low wet areas on my property. Hmmmm where could you get some of them...wait a minute.:hmm3grin2orange:

For real, I would be very interested to know what trees/plants in general "dry up" wet areas.

 

[xtremetrees]

The oldest tree known only drinks about 600 gallons of water a year.
Its almost 5000 yrs old.

 

[elmnut]

I use wood chips in low wet areas on my property. Hmmmm where could you get some of them...wait a minute.:hmm3grin2orange:

For real, I would be very interested to know what trees/plants in general "dry up" wet areas.

willows and red maples can help dry up wet areas, cottonwoods also.

 

[begleytree]

The right trees can help dry up a wet area problem, the local nuke power plant here uses hybrid poplars to dry up a 10 acre area (cooling water discharge), planted 100's of trees.
Talking to them, I found out that they learned that a certian amount of trees dried up the area, but more kept it so shaded, that it remained wet regardless the tree plantings.
-Ralph

 

[smokechase II]

just one view

Locally it has been widely taught that a fair sized juniper, a dry land species, will use up to 70 gallons of water a day if it is available. (They sit dormant for extended periods and then take advantage of what they are given. They live in areas where 4-6 inches of rain/year is the norm.)

A common way to restore a spring for ranchers in eastern Oregon is to cut all/most of the juniper in the bowl above the former spring. (Fire was the primary controller of juniper, remove fire in the last hundred years and "The Juniper Incursion" happens. Exit year round springs.)
OSU scientists just did a study on this in a few different sites and verified juniper removal as a way to restore spring flow.

This was viewed as; "what else did you expect?" Ranchers had this figured out long before dem city-fied university boys came along.

I haven't a clue as to other species and how complicated this could become in different settings.

 

[stumpy66]

If the trees are close to the house and taking up water...they should bear in mind that removing the trees may cause the ground to swell or heave. Giving their building the opposite problem to subsidence.....

 

[clearance]

I have cut down some big cottonwoods, often water just starts gushing out like a cut hose, crazy, all over my pants, running down the stump. A big cottonwood, like 100' + and 3' d.b.h. must pull hundreds of gallons a day, never seen that from any other tree.

 

[rfwoodvt]

Great info but....

ThanX for the input, but seriously, does anyone have any thoughts, formulas, rules-of-thumb or references to how much water a tree can pull from the ground?

My customer is aware of all that has been stated in the replies but what they want is to let the potential home buyers know, that the trees do the bulk of the water removal and approximately how much water the can/might be able to remove.

The idea is to encourage the new home owner to consider that the trees ought not be taken down with a light decision.

 

[smokechase II]

contact

For tree water usage.
The only place I can suggest to go to is a local extension agent from the University in the area that does ag stuff for your state.

Good luck.

 

[Stumper]

I can't imagine any super accurate formula due to the variables. There are transpiration rate studies but not only is calculating total leaf surface full of guesses and average estimates, the actual transpiration rate is constantly varying with light levels, ambient humidity and stomata that are opening and closing for reasons that we aren't even certain about. There are some studies about x distance of mature Cottonwoods along streambanks decreasing stream flow by Y cubic feet per minute. There are also some documents floating around about Tamarix encroachment drying up shallow lakes in the Southwestern U.S.A. It is all full of estimated figures though.

 

[maxburton]

I've never seen research that can nail down tree water usage. Like someone said before, there are too many variables. Transpiration and tree water usage is still a somewhat mysterious subject.

 

[CraneOp1]

Water needs of a tree

Ponder this: A large shade tree can transpire-lose water through its leaves-up to one hundred gallons or more a day. A medium-size tree maple, for instance, will lose about twenty gallons of water through leaf evaporation during an average eight-hour period. On a hot day, this lose can reach forty gallons. A soaking rain that deposits an inch of water over the area of the tree's root system ( about 1,200 sqf ) will provide the tree with seven hundred gallons of water.

This an excerpt from: The Tree Book, by Jeff Meyer, Host of PBS TV's Tree Stories

Found this book last night at Borders for $2.99

Hope this helps.

 

[alanarbor]

From personal experience with doing Elm injections for DED, I observed large Elms pulling 60 gallons of solution in 30-40 minutes.

 

[rfwoodvt]

Excellent info

ThanX, these are some excellent examples of what I'm looking for.

Clearly my customer's property is a wet site. There is no hiding the fact nor is she trying to. She also has a sump pump in the basement.

She is a very detail oriented individual and has a heart-felt personal relationship with her green-scape. She realizes that upon selling the land she will no longer have that relationship but feels duty bound none the less to both the trees and the future homeowners and to ensure that both will have what she feels they need in order to enjoy the property.

My understanding is that the more reasons she can give to leave the trees in place the more likely it will be that they will be left alone.

So, lacking any hard empirical data, any other anecdotal or suppositional examples out there? :monkey:

 

[Kneejerk Bombas]

Alan's DED example is interesting, I hadn't though of that. If you also consider the DED injections are small holes, spaced about 6", this really only represents a portion of the total ability of a tree to move water.
Some years ago at a trade conference the speaker quoted a study of large Willow trees, and if I recall, he said up to 800 gallons an hour under ideal conditions.
Given the tree injection example, I'd say that is about right.
Stumper's point is well taken, about the huge numbers of variables involved.

 

[antigrassguy]

evapotranspiration and sap flow rates

rfwoodvt, there are many studies that have been done in evapotranspiration and sap flow rates. It really comes down to species and age, sun or solar radiation, wind speed, water availability, root pressure, xylem(outer more than inner)...ect. Harvard University's forest dept(GREAT FOLKS) recently released an abstract in 2006 on this subject. The US air force has some info in relation to phytoremediation(trees for cleaning up hazardous waste) OR if you really want to get nuts contact Dynamax Inc. and get some of their Dynagages that you can buy that will measure the sap flow, in real time, of your customers trees and you could provide a very detailed report of how much water or sap they are moving. As for just one formula the math or algorithm would be huge and is very complex, but they are out there. Happy hunting.

 

[antigrassguy]

links

rfwoodvt, Id post links to this stuff, but dad gum it Im a tree guy not a computer guy and, well I just dont know how. PM me if you want and I might be able to help that way or use a search engine for evapotranspiration rates or sap flow rates would be a good start.