Deep Watering of Older Trees

[W. Watson]

I have a number of Deodoras (mostly Atlanticus) that we've had for 8-9 years. All were planted by a landscaper. They are mostly between 15-18' now. Of all the trees I'm considering the topic of deep watering are about 20 (throw in 1 8' oak, 4-5 maple, douglas firs, 2 crabapples, 2 giant sequoias) in total. The trees are scattered over about four acres with drip lines going out from each line. Our watering system and water availability is such that with the lines there's not much of a chance for regular deep watering. We get lots of winter rain. *Probably" over the years, the trees of concern have not gotten a lot of deep watering under these conditions. They all seem sturdy at this point. No wind has taken any down. We are in the Sierra foothills of Calif at 2700', and have very warm summers outside of Sacramento.

Does it make sense to now do deep watering? I just got kicked into action on other property issues, and started giving this some serious thought. I recently took a hose out to each tree and watered them deeply. I'll probably do it again in early to mid-Oct. Is this worthwhile at this stage? I heard a professional gardner mention that deep watering is usually required in the early years of a tree's growth.

[William Wagner]

I use a soaker hose which is cheap and effective on a timer.

These folks would like to sell you more but the add info is worth a look anyway for options..

[symplastless]

Watson

There is no requirement of trees that you deep water. The non-woody absorbing roots that absorb water with essential elements dissolved in it are most of the time in the upper four inches of soil. The biggest problem during drought is over watering. here is an article on where absorbing takes place.

[len garden]

g'day wayne,

generally mature trees will have found their own water table, the drippers will keep nutrients availabe for the feeder roots which maybe is the best you can currently do? if you want to get more water deeper around the roots maybe look to creating a swale about along the contour lines wher the feeder roots will be, the feeder roots are generally not much furhter out that the drip line.

or for trees that aren't planted along contours then ceata a mni dam at the same point as above these swales etc.,. can be created using bails of hay/straw or a pile of mulch in a row form.

for future plantins consider plantng along contour lines and at the same time as planting install say a 1 or 1/2 meter length of the black plastic ag-pipe with holes in it eitehr side of the tree this will allow you to get water deeper at watering time.

On Sun, 23 Sep 2007 11:38:56 -0700, "W. Watson" wrote: snipped With peace and brightest of blessings,

len & bev

-- "Be Content With What You Have And May You Find Serenity and Tranquillity In A World That You May Not Understand."

[symplastless]

What are these feeder roots you speak of? Trees do not absorb food from the soil. They absorb water and essential elements dissolved in it by way of their non-woody absorbing roots with the help of mycorrhizae and in some cases root hairs. Absorbing can be found here:

[Sheldon]

Agreed. All of a sudden artificially deep watering mature trees will very likely do more harm than good... if it ain't broken don't fix it.

[Kay Lancaster]

This is not something I do for well-established trees unless it's a major drought (< 1/3 of the normal rainfall for the entire season) or if the tree is stressed for some other reason (like the neighbor backed a truck into it.) And then I'll do it once, in October or so.

Kay

[W. Watson]

[Sheldon]

Less water, not more, is what encourages stronger root systems. Deep watering of trees should only be done during extended periods of very short water supply... and then no more than twice a growing season. If a tree needs deep watering more often then that type of tree should not have been planted there. Over watering is far more damaging to trees than the occasional shortage.

[len garden]

all trees have a network root system that is in the upper level of soil below the surface these usually but no always extend to the drip line of the tree they are called the feeder root system as this area in the soil is where the nutrients gather the most, and yes it take bacteria, earth worms and otehr organisms to break that material down so those roots can take up those nutrients to the tree, that is the feeder root system.

On Sun, 23 Sep 2007 19:12:32 -0400, "symplastless" wrote: snipped With peace and brightest of blessings,

len & bev

-- "Be Content With What You Have And May You Find Serenity and Tranquillity In A World That You May Not Understand."

[symplastless]

Good question. The non-woody roots absorb and the woody roots are for support, manufacturing vitamins, storing sugar converted to starch and more.

[symplastless]

Again I repeat. The non-water absorbing roots are most of the time in the upper four inches of soil. Watering deeper than that is not of value.

[symplastless]

Look up "Non-Woody Roots

"Woody Roots"