The pecan tree bears between nine and 17 of the these.

Nov 18, Perhaps a less common concern, and one that particularly affects grafted trees, is pecan scab. If you find dark green or even black spots on the young leaves of the tree, then this could be your problem.

There is little else you can do but seek advice on fungicide, as the pecan scab will spread to the fruits unless you eradicate it/5(K). Sep 03, Second, I’ve seen lots of pecan trees that lose leaves and also limbs when they don’t get enough water.

The leaf fall is most likely a result of the current drought following on the heels of ample Estimated Reading Time: 3 mins. Description. Pecan tree leaves eventually grow up to 12 to 20 inches in length during the growing season, and resemble fern leaves.

Each leaf contains 11 to 17 leaflets. Once the leaves appear, small yellow flowers bloom next, helping to pollinate the tree so that it produces fruit if. Oct 22, Zonate leaf spot, caused by the fungus Cristulariella moricola, causes severe defoliation of pecan trees during July and August of rainy summers. Leaf spots on the upper surface of pecan leaves are grayish brown, with concentric ring formations that are more distinct on the lower side of the leaf.