Caplan’s April Newsletter

Winter Injury on Evergreens

I’ve seen a lot of winter injury on evergreens this spring, especially on arbor vitae, junipers, and rhododendrons. Most of this is desiccation injury. Basically, cold, dry wind wicks the water out of the leaves/needles of evergreens, drying them out. Because of frozen soil or dry conditions, the plant cannot take up enough water to replace the missing moisture. As a result, the foliage turns a bronze/brown color.

Desiccation injury/scorch on rhododendron leaves

Much of this tissue is dead, and will need to be snipped off, but the plant itself is probably going to survive quite well.

There may be other things causing browning needles, including fungal diseases. Please give me a call to check out your plants if you suspect disease or insect problems.

Invasive Species Updates

Spotted Lanternfly

As mentioned in my February newsletter, Spotted lanternfly (SLF) is an invasive insect, related to plant hoppers, that was first discovered in Pennsylvania in 2014. Since then, it has spread throughout much of the east coast and New England. This past year, SLF was found in Switzerland County in southeast Indiana. No new updates at this time, but please check out the picture below for life stages, and please visit Penn State for more information: https://extension.psu.edu/spotted-lanternfly

Asian Needle Ant Found in Evansville

An invasive ant that can deliver a painful sting has been found in Indiana for the first time, a Purdue University insect expert says. The Asian needle ant has traveled southern states like Florida and Georgia for several years. But if was recently discovered in the Evansville area – the furthest north the ant has ventured, said Timothy Gibb, a Purdue University entomologist.

The Asian needle ant is the first ant in Indiana that has a stinger and venom sac, Gibb said. Gibb said that while he hopes people don’t go into a state of panic about the ant’s arrival in Indiana, they should be aware of the dangers the insect can pose. “It can be lethal.” he said. “In most cases, it’s just going to hurt like crazy.”

For most people, stings from the Asian needle ant will not be harmful, just painful. But people who are hyper=allergic to stings from insects like bees or wasps should be prepared with treatment such as an EpiPen.

The Asian needle ant can infest homes as well as woodland and outdoor areas, putting them in close proximity with people. Because the ant can infest homes, that will increase its ability to survive in Indiana’s cold winter temperatures by protecting it from the extreme cold.

More information on needle ants from US Forest Service: https://www.srs.fs.usda.gov/pubs/su/su_srs143.pdf

Information on controlling ants indoors and outdoors, from University of Kentucky: https://entomology.ca.uky.edu/ef619

My take on this: these Asian needle ants are not as dangerous or aggressive as fire ants; however, local gardeners should be on the lookout for stinging ants. Be advised that you probably can’t pick up a random ant and identify it as this new invasive species (unless it stings you, of course); however, if you do run into a nest of stinging ants, scoop some up in a jar, stick it in a freezer to kill them, and either report them using the EDDMapS website or app (https://www.eddmaps.org/report/), or contact the DNR: Phone: 1-866 NO EXOTIC (1-866-663-9684); E-mail: depp@dnr.IN.gov.

A Caterpillar By Any Other Name…

The caterpillar pictured above has been known as the Gypsy Moth for well over 100 years. Its scientific name is Lymantria dispar. Recently, the Entomological Society of America changed the common name of to “spongy moth.”

These caterpillars are extremely destructive, and are found throughout the northeastern US. In Indiana, they are restricted to the northeast part of the state. To date, they have not been found in southwestern Indiana. If you ever see a hairy caterpillar with 4 pairs of blue dots, followed by 6 pairs of red dots, contact me, your local extension office, or the DNR/invasive species group listed above in the section on stinging ants.

Poison Hemlock greening up now

Poison hemlock is a biennial weed that is commonly seen in our area, growing along roadsides and in vacant fields. All parts of this plant are poisonous. Coming in contact with the sap can cause severe rashes.

This plant is most easily controlled by mowing it down before it blooms and sets seeds. If you are using weed-eater, be sure to wear gloves and eye protection, as the sap spreads everywhere. A number of herbicides can also be used in mowing is not an option, but again, it must be done now, before the plant goes to seed.

It’s Still Time for Pruning!

If you have fruit trees or small ornamental trees (dogwoods, Japanese maples, etc.) that you want to have pruned, there’s still time to have me come out and do the work. While I usually prefer to do my pruning during the dormant season, it won’t hurt the plants by doing this work now. Please contact me to get a free quote for the work.

If you have large shade trees that need pruning, you need to have a tree company that is licensed with the City of Evansville. For a person/business to prune or remove trees for hire within the City of Evansville, whether on public or private property, they must have a license. If the company does not have a license it means they do not have the appropriate insurance. A list of licensed companies in Evansville can be found here: https://www.evansvillegov.org/egov/apps/document/center.egov?view=item;id=2020