Native Plants

Q. Who is Mr. Smarty Plants?
A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.
Did you know you can access the Native Plant Information Network with your web-enabled smartphone?
Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

rate this answer

Wednesday - July 10, 2013
From: Dripping Springs, TX
Region: Southwest
Topic: Diseases and Disorders, Pests, Trees
Title: Spots on persimmon tree leaves from Dripping Springs TX
Answered by: Barbara Medford
QUESTION:
We are in rural Hays County Texas off Hamilton Pool Rd Texas. Large persimmon trees are turning yellow, blackish spots on underside of leaves. What do we do?ANSWER:
According to this USDA Plant Profile Map, Diospyros texana (Texas persimmon) is native to Hays County. We always check this first in case the problem cited might be a result of climate or rainfall, as well as incompatible soils, that is causing that problem.
Because the symptoms you describe could be caused by several different problems, we are going to link you to some articles and pick out some material to quote that seems to address your particular situation:
eHow Home Persimmon Tree Diseases and Pests
"Leaf Spot
-
Another disease that infects common persimmon is leaf spot. Leaf spot, or anthracnose, is caused by the fungus colletotrichum. Although not deadly to adult trees, leaf spot does cause black spots to appear on the surface of leaves, and may sometimes affect fruit as well. It can also lead to early dropping of leaves--this is most noticeable in August, for the North, and September, for the South. Sprays containing baking soda or sulfur, or the pesticide Bordeaux mix, are commonly used to control it.
University of Kentucky Cooperative Extension American Persimmon (as opposed to non-native Oriental Persimmon)
"There is interest in varieties that have leaf spot resistance. Persimmon wilt, a fungal disease due to Cephalosporium diospyri, has caused considerable damage in the south."
All that having been said, we have suspected aphids from the beginning. This article from the University of California Integrated Pest Management on Aphids includes this statement:
"Low to moderate numbers of leaf-feeding aphids aren't usually damaging in gardens or on trees. However, large populations can turn leaves yellow and stunt shoots; aphids can also produce large quantities of a sticky exudate known as honeydew, which often turns black with the growth of a sooty mold fungus. Some aphid species inject a toxin into plants, which causes leaves to curl and further distorts growth. A few species cause gall formations."
This article also has information about control. Notice that the presence of ants on the tree usually indicates aphids. The ants don't damage the plant, but they are farmers, gathering the "honeydew." The last line on the paragraph on Management is:
"Managing ants is a key component of aphid management."
Since we are not plant pathologists, we recommend you contact the Texas A&M AgriLIFE Extension Office for Hays County.
From the Image Gallery
More Diseases and Disorders Questions
Smarty Plants on lantana in Dallas
September 14, 2005 - For several years, the lantana plants in my backyard in Dallas grew and bloomed all Summer and Fall until the first real cold snap. I've loved having a native plant that didn't need constant care a...
view the full question and answer
Mountain Laurel having trouble in AZ
June 07, 2011 - A Sophora secundflora (Texas mountain laurel) was planted to an Arizona north faced front yard last year in August under full sun. Starting early this year, I noticed its leaves turn to light green an...
view the full question and answer
Wilting American Smoke Tree in Texas
April 21, 2013 - I planted a young American smoke tree last fall (mid-November) and it put out a good show of tentative new leaves this spring. Then to keep the tree form I clipped some little shrubby start ups at the...
view the full question and answer
Verticillium wilt in catalpa and maple
July 17, 2008 - On Monday - July 07, 2008, you answered a question about a catalpa and maple with the same problem--an entire branch died, and then more of the tree died. And both trees came from the same nursery. Th...
view the full question and answer
Declining wax myrtles in Katy, TX
August 24, 2009 - My wax myrtle bushes were thick and green except for a few on the NE side 6 months ago when we bought the house. Now they are thin, leggy, and dropping leaves like crazy. They seem to be dying one bra...
view the full question and answer
Support the Wildflower Center by Donating Online or Becoming a Member today. |