z,
Any chance that these abnormal leaves are on branches arising from the rootstock, and not the grafted Seckel variety?
Seckel fruits here are past their prime, and I'm in zone 6. Your remaining pear fruit may be over-ripe now.

The branches are well above the graft.

The tree has been so healthy and now I'm concerned that a slow disease has been working on it since Spring.
There are a lot of ants that have made their home under the tree since before last year. Is it possible that the ant colony is so large under the ground that the tree is not getting nourished properly? Last summer was so dry and we have not completely recovered from the drought in our area.
I never watered our pears or apples as they were surviving OK. The other fruit trees (2 other pears and 4 apples) do not have whatever this problem is.
zinia

Zinia:

Leaf dwarfing on a pear tree is a very unusual symptom, and I have to confess I am unable to explain it. I think it is worth the wait to see what it does next season, and if it repeats this performance that may be the time for concern.

I am not familiar with the type of fertilizer you used, but find it hard to believe that could be responsible for the leaf dwarfing. In general, however, pear tree do not require application of chemical fertilizers in soils of reasonable fertility. Mine receive only the small shot from fertilization of the lawn the surrounds them, and I do mulch the trees about every three years. Nor do pear trees normally require much in the way of spraying, unless they are plagued with something like pear psylla, which causes black spotting of the leaves. I have not sprayed the European or Asian pears at all this season, and they are just fine, although I do spray them with dormant oil each winter.

If you want to get rid of the ant colony, drench the soil with a permethrin solution or use permethrin granules. Your tree will not be injured, nor will you be poisoned by this particular insecticide, especially when applied to the soil.

Don Yellman, Great Falls, VA

Zinia, that is probably a disease. I had something which sounds the same on one of my pears this spring. I had it on only a couple limbs and I chopped them off and it got better. I think it may be a disease called pear decline phytoplasma which the pear psylla (little bug smaller than an aphid) transmits. There is no known cure for the disease but the trees will often "grow out" of it, somehow learning to adapt to it. I would much the tree very heavily with compost to make sure it is getting good nutrients and water, and hope it starts to recover next year.

Scott

Here is a link that might be useful: Pictures of pear decline

Thanks very much for all the help.

I would like to mulch, but I keep hearing that it's a "hide-out" for insect pests and rodent pests. Is there a safe way to mulch--like placing it so many inches from the trunk?

Although I mentioned concern about the ants living under the tree, I wonder if their tunnels provide air and water.
Should I just get ride of them in case they are helping to destroy my tree?
zinia

I have mulched hundreds of trees right to the trunk without any ill effects. If you are worried about it, keep the mulch far enough away to not touch the trunk.

I have many thousands of ants in my orchard and just let them do their ant thing. Their primary annoyance is when they move aphids around but besides that I have not noticed any ill effects.

Scott