Monthly Help Desk Report by Kathy Love
Well over 50% of calls to the BCMGA Help Desk are tree and lawn concerns, but the runner-up to those two issues is insects, most generally insect identification.
While tree concerns from freeze damage continues to dominate calls to the BCMGA Help Desk, July and August both saw an uptick in citizens requesting insect identification. With the help of a good loop, blowups from our smart phones and Google lens, we were able to identify everything that came in.
The Milkweed photos came in from two different citizens. The first photo in this set is of the insects on a milkweed pod. Pretty good give away for the Milkweed Beetle or Longhorn Milkweed Beetle. Photo 2 in this set is identified as the nymph stage of this insect and photo two, taken from a swarm on an oak tree is one of the later instars, probably 2nd from size and markings, as they have 5 instars in their life. The adult beetle, is the last instar of the Milkweed Beetle. The advice from the Missouri Botanical Gardens for control on Milkweed is to live with them as they do little damage and are only present for a short period of time. Sanitation will help with overwintering and insecticidal soap is effective if you get good coverage on the insects. Chemical control is discouraged to avoid harm to beneficials.
The spider photo came from a citizen whose concern was damage to her oak trees. We thought probably insect damage but asked for some specimens. Damage to the undersides of the leaves and the presence of honeydew confirmed our thought the damage was principally aphids. But we spotted an unidentified live insect on her specimen that was NOT an aphid. Upon close up inspection we found it to be a Jumping Spider—not damaging to her tree but there most likely hunting the suspected aphids.
We can’t have a summer without the ever-present fall Armyworms seen (left) in photo four. To identify these pests, we look at the color, they range from shades of brown to gray, green, or yellow-green, and their most distinguishing characteristics-a whitish inverted Y between the eyes and three whitish stripes on the pronotal shield behind the head. For a complete list of products labeled for fall armyworm control, we suggest that citizens consult the Texas Turfgrass Pest Control Recommendations Guide.
June and July
In June and July, the desk has logged 9 contacts from citizens concerned they have seen the recently publicized Asian Giant (Murder) Hornet (AGH) Vespa mandarinia. In all but one instance we were able to assure the concerned citizens they were seeing either the Eastern Cicada Killer Sphecius speciosus (7 calls), the Western Cicada Killer Sphecius grandis (1) or in 1 case a bald faced hornet Dolichovespula maculata… Read More
Citrus – Hardy Orange
October 9, 2020 – An Interesting Help Desk Citrus question
answered by Ann Wagner 2016 Certified Master Gardener.
This article pertains to a citrus call received at the Master Gardener help desk. It is worthy of an article because of the nature of the call–a prolific citrus tree in a yard across from Mary Hardin Baylor. The call came in on October 9th and the caller was concerned about imperfections on the peels of his prolific lime trees and something not right with the taste of his limes.
Being a graduate of University of Florida and having taken numerous citrus courses I thought it very unusual for there to be a fifteen foot tall lime tree in Bell County Texas. Upon returning the call the property owner agreed to a site visit. I found there were two trees, which were full of citrus fruit and indeed about fifteen feet tall. They looked healthy. They did look like limes until I noticed two characteristics which were not present in the photos we received.
The citrus trees had numerous long spikes on the branches and a fruit that had been on the ground was yellow orange and the leaves on this citrus were shedding. These were all things that I observed and are indicative of Trifoliate Orange or Hardy Orange It is the only citrus tree that loses its leaves in the Fall. After we cut open the fruit , I saw that these were not limes, but rather Poncirus Trifoliata which is the scientific name. The fruit pulp did not look green enough to be a lime, it did not smell like lime or lemon and the taste was terrible. There were about 10 large seeds in each fruit. The leaves were compound with winged petioles. .Having seen these growing on the University of Florida campus as well as growing wild in the wetlands around Nacogdoches, Texas where I was a Soil Conservationist; I was able to deduct that these were indeed Trifoliate Orange or Hardy Orange. Strange enough, Trifoliate Orange is not used for its fruit and it is too thorny to grow around pets or people, so why this man had two of these originally bought from Lowes seven years ago is still a mystery.
In the citrus industry, Trifoliate Orange is used as a rootstock for orange and grapefruit to make them cold hardy . The rootstock is cold hardy down to sub zero and has been cultivated for thousands of years from Northern China to Korea. It was introduced in the US during Colonial times for livestock fencing due to its large thorns. What I find interesting about this site visit in Belton is how these two trees are growing so well in soil that is most likely alkaline. The Texas ArgiLife Extension website states that the Trifoliate Orange does not do well in alkaline or saline soils.
After doing additional research on the Hardy Orange on the North Carolina State University Extension site (https://plants.ces.ncsu.edu), I learned it is considered somewhat invasive due to its prolific fruits which produce many large seeds which birds disperse. It grows best in acidic soils and in hardiness zones 5 to 9.
BCMGA Mission Statement
The Bell County Master Gardeners Association assists the Texas A&M AgriLife Extension Service in providing high quality, relevant, research-based horticultural education and service to the residents of Bell County and the state of Texas through outreach, teaching, and demonstration projects.