Horticulture Fall 2023 Newsletter

Horticulture Fall 2023 Newsletter

Horticulture Fall 2023 Newsletter

October 2023 Edition

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Horticulture Newsletter Fall 2023 “Around and About the Garden with Annette”

Enjoy the fall weather and working in the garden.

• Many locally grown pumpkins, gourds, and flowering plants are available for sale for fall decorations.

• Harvest pumpkins from the garden when the rind has hardened and they have a deep solid color.

• Bring houseplants that have spent the summer outside inside. Check for insect pests, treat with appropriate method or insecticide outside before bringing indoors.

• Bring succulents inside unless they are hardy to Zone 6. Succulents from the genus Sempervivum are hardy to Zone 6.

• Radishes can be planted in the garden or container through October 1.

• Harvest sweet potatoes when they reach a usable size. Dig a hill to check on size.

• Fall is the best time to test the soil in the vegetable, flower garden, landscape, or the lawn. Collect soil for a soil test to determine if phosphorus, potassium, or lime are needed. Soil tests are free to Daviess County residents due to a grant from the Daviess County Soil Conservation District. Soil testing basics can be found on the Daviess County Cooperative Extension Service website at https://daviess.ca.uky.edu/testing-identification.

• Plant spring flowering bulbs, including daffodils, tulips, and crocus.

• Remove weeds before they produce seeds.

• Autumn is a good time to plant most trees and shrubs.

• Dig and store tender bulbs such as cannas, elephant ears, dahlia, and gladiola after the first frost.

Tips From Annette
Thursday, October 12, 2023

Create a Fall Pumpkin Arrangement
at Daviess County Cooperative Extension Service Office at 10:00 a.m. and 6:00 p.m.

Thursday, October 12, 2023
”All About Herbs.”
Guest speaker, Peggy Thieneman will present at Daviess County Cooperative Extension Service Office at 1:00 p.m.

Tuesday, November 14, 2023
Commercial Pesticide Training
at Daviess County Cooperative Extension Service Office 8:00 a.m. to 12:00 noon.
This free program provides CEU’s.
Please RSVP: 270-685-8480.

Tuesday, November 14, 2023
“What to do About Emerald Ash Borer in Daviess County.”
At Daviess County Cooperative Extension Service Office 1:00-2:00 p.m.

By: Simone Lewis, National Weather Service Charleston, WV

When the word wildfire comes to mind, images of burning forests in the western United States usually enter the thoughts of most. But did you know that Kentucky is also prone to wildfires? In fact, the state averages 1,447 wildfires a year! The following article will discuss what weather conditions are favorable for wildfire development, the weather alerts that are issued during periods of favorable fire weather, and what you can do to prepare for and prevent wildfires.

The first question on your mind is probably “What is Fire Weather”? Essentially, fire weather is any sort of weather that can ignite or lead to rapid spread of fires. This includes thunderstorms (which contain strong gusty winds and lightning that can lead to rapid spread or ignition of a fire), days when the relative humidity is low (often in the early spring and fall seasons), and windy days (which acts to not only spread wildfires but also leads to the drying of vegetation, making it more susceptible to burning).

Wildfire Prevention

Most wildfires in the state of Kentucky are caused from arson or from uncontrolled debris burning. In fact, 90% of all wildfires in Kentucky are caused by humans. Unlike many fires in the western United States, most of the fires in Kentucky are fought by firefighters on the ground (Source: Kentucky Energy and Environment Cabinet). They are putting their lives in danger to control the spread of these fires. It is therefore important to always be fire aware, and heed any Fire Weather Watches or Red Flag Warnings issued by the NWS.

Here are some general guidelines to follow when the following products are issued:

Fire Weather Watch = BE PREPARED! Dangerous fire weather conditions are possible in the next few days but are not occurring yet.

Red Flag Warning = TAKE ACTION! Dangerous fire weather conditions are ongoing or expected to occur shortly. During a Red Flag Warning, you should avoid or use extreme caution when dealing with anything that could pose a fire hazard.

• Do not start a campfire or ignite a burn pile.

• Do not burn trash

• Avoid using a lawnmower, chainsaw, or any other equipment that may emit sparks.

• Do not dispose of cigarette butts on the ground or outside of your car. ashes until the Red Flag Warning has expired or been canceled AND the ashes are fully extinguished!

What do I do to prepare?

Take personal responsibility by preparing long before the threat of a fire, so your home and family are ready.

• If there are concerns of fire potential, create a defensible space by clearing brush that is easier to ignite away from your home.

• Put together a basic emergency supply kit. Check emergency equipment, such as flashlights and generators.

• Plan escape routes and make sure all those residing within the home know the plan of action.

• Sit down with your family and close friends, and decide how you will get in contact with each other, where you will go, and what you will do in an emergency. Keep a copy of this plan in your emergency kit, or another safe place where it can be accessed in the event of an emergency.

• Review your insurance policies to ensure that you have adequate coverage for your home and personal property in the event of fire.

• Follow the latest NWS forecasts and listen to a NOAA Weather Radio for the latest updates.

What are Kentucky’s Fire Laws?

Lastly, it’s important to know and heed the fire laws and seasons for the state of Kentucky. During the following periods, it is illegal to burn anything within 150 feet of any woodland or brushland between the hours of 6 a.m. and 6 p.m.

• Spring Forest Fire Hazard Season: February 15 - April 30

• Fall Forest Fire Hazard Season: October 1 - December 15

Also, burn bans can be issued at any time of the year if conditions warrant, particularly during periods of drought, and should always be followed.

By: Lee Townsend, Extension Entomologist, Professor Emeritus
Kentucky Pest News, September 2017

Several web-making caterpillars can be active in late summer. They cooperate to bind leaves and branches together into unsightly, but protective, nests where the can feed more or less undisturbed. Species active at this time of year include the relatively common fall webworm, the specialist mimosa webworm, and the relatively uncommon ugly nest caterpillar. Usually, they cause scattered aesthetic injury, but occasional outbreaks can be destructive.

Fall Webworms

Fall webworms are fuzzy caterpillars that have pale green or yellow hairs over their bodies and rows of black spots along their backs. They cooperatively build light gray tents (Figure 1) that enclose the ends of branches of over 100 species of forest trees, shade trees, and shrubs; sourwood, pecan, and persimmon are favorite hosts. Fall webworms feed on leaves inside the webbing and expand the “tent” as they require more food during their 4- to 5-week developmental period. There are two generations of the mimosa webworm each year; the second generation can cause severe defoliation, especially to thornless cultivars. Fall webworms are primarily an aesthetic issue on healthy, established landscape trees. However, significant infestations on stressed or new transplants can be serious.

Mimosa Webworm

Mimosa webworm caterpillars generally produce smaller webbed areas than fall webworms but can make up for it in intensity of infestation (Figure 2). Larvae feed primarily on mimosa and honeylocust. Full-grown gray to dark brown caterpillars have five narrow stripes running from head to tail. Mature caterpillars (about 0.6 inches long) can be nuisances as they rappel down silk threads onto unsuspecting passers-by walking below infested trees. There are two generations of mimosa webworm each year; the second generation can cause severe defoliation, especially to thorn-less cultivars.

Ugly Nest Caterpillars

Ugly nest caterpillars are yellow-green with black heads. They inhabit seemingly slapped-together nests that resemble those of the fall webworm. Full of brown leaves and dark, granular frass, the few nests that occur each season tend to be widely scattered and serve only as minor eye-sores.

Individual webs have little impact on tree health and can be left to natural enemies. An insecticide spray may be needed if the first generation of mimosa webworm is causing noticeable damage, usually during June. This reduces the potential for a larger and more damaging second generation during August and September. Products containing spinosad or pyrethroids can work as contact or stomach poisons. Treatments can be focused on the foliage in and around the tent. Usually, there is no need to spray entire trees.


By: Zachary DeVries, Entomology Extension Specialist
Kentucky Pest News, September 2023

Many pests seek refuge in homes and buildings in response to changes in weather, such as extended periods of rain or drought, or the onset of cool autumn temperatures. In response to these pest invasions, homeowners often apply liberal amounts of insecticides indoors. Although indoor insecticide application often provides quick results for the pests you see, this strategy is generally ineffective at providing a long-term solution because most of the pests being treated are coming in from outside the home. Therefore, to ensure a pest-free home, it is important that residents focus their attention towards denying pest entry before they make their way indoors, a process better known as “pest-proofing”. Outlined below are six tips for pest-proofing one’s home or business. The suggestions in the first three bullets will also conserve energy and increase the comfort level during winter and summer. Equipment and materials can be purchased at most hardware or home improvement stores.

Install door sweeps or thresholds at the base of all exterior entry doors. Lie on the floor and check for light visible under doors. Gaps of 1/16 inch or less will permit entry of insects and spiders; 1/4-inch-wide gaps (about the diameter of a pencil) are large enough for entry of mice; 1/2-inch gaps are adequate for rats. Pay particular attention to the bottom corners as this is often where rodents and insects enter. Garage doors should be fitted with a bottom seal constructed of rubber (vinyl seals poorly in cold weather). Gaps under sliding glass doors can be sealed by lining the bottom track with 1/2- to 3/4-inch-wide foam weather stripping. Apply sealant (see “Seal cracks” below) along bottom outside edge and sides of door thresholds to exclude ants and other small insects.

Seal utility openings where pipes and wires enter the foundation and siding, such as around outdoor faucets, receptacles, gas meters, clothes dryer vents, and telephone/cable TV wires. These are common entry points for ants, spiders, wasps, rodents, and other pests. Holes can be plugged with mortar, caulk, urethane expandable foam, copper mesh (like the material in pot scrubbers), or other suitable sealant.

Seal cracks around windows, doors, fascia boards, etc. Use a good quality silicone or acrylic latex caulk/sealant. Although somewhat less flexible than pure silicone, latex-type caulks clean up easily with water and can be painted. Caulks that dry clear are often easier to use than pigmented caulks since they don’t show mistakes. Buy a good caulking gun; features to look for include a back-off trigger to halt the flow of caulk when desired, a built-in ‘slicer’ for cutting the tip off of new caulking tubes, and a nail for puncturing the seal within. Prior to sealing, cracks should be cleaned and any peeling caulk removed to aid adhesion. For a professional look, smooth the bead of caulk with a damp rag or a moistened finger after application. A key area to caulk on the inside of basements is along the top of the foundation wall where the wooden sill plate is attached to the concrete foundation. Ants, spiders, and other pests often enter through the resulting crack.

Repair gaps and tears in window and door screens. Doing so will help reduce entry of flies, gnats, mosquitoes, and midges during summer, and cluster flies, lady beetles, and other overwintering pests in autumn. Certain insects are small enough to fit through standard mesh window screen. The only way to deny entry of these tiny insects is to keep windows closed during periods of adult fall emergence.

Install 1/4-inch wire mesh (hardware cloth) over attic, roof, and crawl space vents in order to prevent entry of birds, bats, squirrels, rodents, and other wildlife. Be sure to wear gloves when cutting and installing hardware cloth as the wire edges are razor-sharp. Backing the wire mesh from the inside with screening will further help to prevent insects such as ladybugs, paper wasps and yellowjackets. If not already present, invest in a chimney cap to exclude birds, squirrels, raccoons, and other nuisance wildlife. Raccoons, in particular, are a serious problem throughout Kentucky. Many chimneys become home to a family of raccoons which, in turn, are often infested with fleas.

Consider applying an exterior (barrier) insecticide treatment. While sealing is the more permanent way to exclude pests originating from outdoors, comprehensive pest-proofing is laborious and sometimes impractical. For clients needing an alternative, pest-proofing can be supplemented by an exterior treatment with an insecticide. Homeowners will get the most for their efforts by applying longer-lasting liquid formulations containing pyrethroids (e.g., cypermethrin, bifenthrin, cyfluthrin, Gamma-Cyhalothrin, etc.). Such products are sold at hardware and lawn and garden shops. For better coverage, it’s often best to purchase these products as concentrates so that they can be diluted and applied with a pump up sprayer, hose end sprayer, etc. Treat at the base of all exterior doors, garage and crawl space entrances, around foundation vents and utility openings, and up underneath siding. It also may be useful to treat around the outside perimeter of the foundation. Be sure to follow all label instructions, and use this information only as general guidance. Clients who choose not to tackle these activities may want to hire a professional pest control firm, many of which offer pest-proofing services.

By: Annette Meyer Heisdorffer, PhD, Horticulture Agent

By following proven practices for planting trees and shrubs, they establish faster and provide years of enjoyment. These practices include:

• Select growing site carefully. Make sure plant has enough room to grow. Watch for power lines.

• Plant in the fall to optimize root growth before the growing season.

• Call 811 before digging to mark underground utilities.

• Conduct a soil percolation test at the planting site to determine how well the soil drains. Instructions on how to conduct the test are available at http://www2.ca.uky.edu/agcomm/pubs/ID/ID237/ID237.pdf.

• Determine which tree or shrub will grow best in the planting site considering the amount of sunlight it will receive and the soil drainage.

• Dig planting hole twice as wide as the diameter of the root ball at a minimum.

• Dig the planting hole the same depth as the root ball. Excessive planting depth causes the roots to suffer from low oxygen levels, excess water, and root rot, which can lead to plant death. Find the root flare and/or the first roots to determine the depth.

• Score the sides of the planting hole with a shovel to prevent slick side walls where roots are not able to grow into the soil.

• Remove wire baskets and burlap from balled-and-burlapped trees after the three is set in the planting hole.

• If container grown, disturb roots by pulling them apart, straightening large circling roots, or making 1” deep vertical cuts in 4-6 locations around the root ball to prevent the roots from continuing to circle in the planting hole and not grow into the soil.

• Fill the planting hole with only the original soil that came out of the hole.

• Backfill hole until it is half full. Tamp lightly and water thoroughly. Continue adding more soil a few inches at a time, water, and let the soil settle.

• Do not fertilize until after the plant is in the new location for one year, and then apply fertilizer in the fall.

• Do not prune plant to compensate for root loss. Only corrective pruning to remove crossing limbs and double competing branches for the center of a tree.

• Apply mulch no more than 2-3 inches deep over root zone and not against the trunk.

• Water the plant as needed by feeling down into the soil. Too little or too much water can kill the plant. Avoid every day light waterings to discourage roots from remaining shallow and dependending on you. Water one to three times per week depending on the soil.

More information about planting trees and shrubs properly can be found in the publications:
“Planting Container-Grown Trees and Shrubs in Your Landscape”, “Planting Balled and Burlapped Trees and Shrubs in Your Landscape”, and “Transplant Shock: Disease or Cultural Problem?” on the web at https://daviess.ca.uky.edu/horticulture.

Tox-Away Day
Saturday, October 7, 2023
8 a.m. to 12 noon

A free drop-off of household hazardous waste will be held at the Daviess County Operations Center (2620 KY-81)