Care of apple trees

[Tsivya]

This is the first year that I am taking care of the yard work at my house. I have 1/3 acre near Denver, which has a terrible drought. Watering is limited to two two-hour periods a week.

27 feet below my house elevation is a creek (which will probably dry up before the summer is over). I have two enormous pine trees which are halfway up to the house.

Questions:

Do I need to water the trees, or are they all drawing from the water table that holds the creek? There are apple trees on the side of the house and in the upper back.

One apple tree is losing leaves; they are turning yellow and dropping off. Another apple tree has a white substance I've never seen before, mainly on the joints where the leaf stems attach to the tree. Is this a disease? Can it be treated?

One of the large pine trees has dead branches at the bottom. Is this normal or a sign of ill health? Do I need to cut them off? (One of them gave me a black eye a couple of weeks ago.)

It appears that all of the elm trees have Dutch elm disease, and I'm starting to take them out. A couple of those trees are very, very large. Is there any special way I need to dispose of the diseased trees?

How do I care for trees in a drought?

 

[Stumper]

Yes you should water the trees.

Are the yellow leaves on your apple on the interior of the tree or on the branch tips?

Is the white substance dry or wet and frothy?

Lower limbs dying on a pine is common/normal (depending on circumstances). If they are dead cut them off.

What symptoms are the Elm trees displaying? What variety of elm are they? If they do have Dutch elm disease (which I tend to doubt) haul them away.

The most important care for your trees during a drought is supplemental watering. Your current restrictions of 2 hours twice per week should prove adequate.

 

[John Paul McMillin]

the white substance on your apples could be aphids, spray with an insecticidal soap or high pressure of water if they arent that bad, and the limbs turning could be from drought or fireblight .

 

[Tsivya]

Thank you so much for your response.

Unfortunately I can give you only wishy-washy answers.

The apple tree with the white stuff on it has yellow leaves closer to the trunk and (as far as I can tell) only at the bottom. The white stuff looks like cotton. It was damp, but then we had a little shower a couple of hours ago.

The other apple tree has yellow leaves which seem to be more towards the tips of the branches, and I didn't see any white stuff. Also, the yellow leaves extend higher up in the tree.

I don't know what kind of elm trees I have. Patches of the leaves turn brown.

With regard to watering, I can't even get the LAWN watered in that amount of time! If I set up more hoses, the water pressure drops.


What is fireblight?

 

[John Paul McMillin]

sounds like wooley aphids to me they look like cotton. Fireblight is a bacteria that only affects plants in the Rose family. Have it tested if you want to know for sure with your local university extention service. when pruning clean your shears with Lysol or bleach after each cut. Fireblight usually will brown the ends of the new growth and they will turn black and have a crook on the end . It will look like the branch was burned sometimes.JPM

 

[John Paul McMillin]

Trees need 1 inch of water per week. if you dont get that with rain then i would soak the soil under your trees , especially trees planted within the last year or two.

 

[ByrdzEye]

Given a choice between saving the trees and saving the lawn, consider which is easier, quicker and less expensive to replace.
I would let the lawn go, save the trees.

 

[FBerkel]

Sounds like the apple with interior yellowing is suffering from drought, the one with yellowing at the tips may well have fireblight. Blighted trees' leaves turn yellow first, then brown. It is almost always advisable to wait until dormancy (winter) to prune out fireblight infections. If you do take a sample, make it a very small one. It can be very hard to wait for six months while a tree seems to be crying out for care, but the research (and my experience/observations confirm it) indicates you should wait.
When the time cames to prune, you must look for the cankers (sunken, discolored areas on stems), and prune a good 8 inches below them. Pruning cuts should be made either at major stems from which the infected branch emerges, or significantly sized lateral branches (offshoots). Sanitizing (ok, jps?) may or may not be necessary, but is not hard to do. I've always heard that 10% chlorox is better than alchohol.

 

[Stumper]

Your getting lots of good advice. The white stuff on your apple may be cottony mildew-if so it can simply be washed off. (The advice to spray wtih insecticidal soap is still good advice -it is pretty safe stuff and gives harmful insects fits )

The browning of your elm leaves is probably(based on the calls I get here in Canon City) the result of Lace beetles feeding on the leaves. Do the leaves have areas between the veins eaten away? If it is the work of lace beetles it is unsightly and certainly stresses the tree but unlikely to prove fatal. You can spray for the beetles but it is difficult to control them-as soon as your spray is washed away more beetles show up from somewhere upwind .