After a very wet and warm spring, June has arrived. If you haven’t checked your trees and shrubs, now is the time. You’d be surprised how quickly insect infestations or diseases can take over and severely damage bushes and trees. Two insects to keep an eye out for in June are bagworms and Japanese Beetles.
Bagworms attack both deciduous trees and evergreens, but their favorite plants are juniper, arborvitae, spruce, pine, and cedar. They are easy to spot if you know what you’re looking for. They come from caterpillars that hatch out of their cocoons and hang in small sacks around the end of May. They feed on the leaves and buds. They look like tiny pine cones hanging from the plant. But inside that bag is the female bagworm and, depending on the time of year, all of the eggs she has laid.
June Is the Time to Treat Bagworms
Adult bagworms can be cut off with a knife or garden shears, but be sure to cut the silk band that holds them to the branch so it doesn’t remain and girdle the branch. This works well with small infestations on smaller trees and bushes. But many times, infestations can be widespread or occur on taller trees. Then, spraying is your best choice. The best time to spray is June because the small larvae are more vulnerable to treatments.
Japanese beetles are copper and green beetles about a half inch in length. They lay eggs in the soil in June and emerge a year later as adult beetles and start feeding on just about anything in sight. They will attack over 300 different types of plants. Unfortunately, they usually attack in groups which means damage can be sudden and severe. They are voracious and can completely strip the foliage from your plants. The adult Japanese beetle life cycle is not long, (barely 40 days), but they can wreak havoc in that short timeframe. In Kansas City, they have been showing up at the end of June and early part of July.
Signs to Look For
Skeletonized Leaves and Flowers – Japanese beetles feed on the foliage, so look for leaves that are “skeletonized” (all of the green is gone and only the veins remain to hold the leaf together). Also look for the beetles themselves – shiny, iridescent copper and green. Adult beetles bang into window screens at night and crawl around the sidewalks first thing in the morning.
Unhealthy, Brown Patches in Lawn – Japanese beetle grubs (larvae) eat the roots of the grass while overwintering in the soil. Look for brown patches of dead or dying grass in the lawn. This shows up later in the summer – usually late August and early September. The damage is similar to classic grub damage from June bugs. The grass will pull up easily because the roots aren’t holding it to the ground.
How to Treat Japanese Beetles
Hand Pick – The easiest way to rid your plants of these pests is to hand pick them. Get a bucket of soapy water (pour a tablespoon of liquid dish soap into a gallon of water) and throw them in as you pluck them from the plant. This will cause them to drown.
Pro Tip: Lay a tarp or drop cloth under the plant and shake it. Many will fall off and you can easily scoop them up and throw them in the bucket.
Pro Tip: DO NOT USE the pheromone/trap bags that the garden center or hardware store sells. They will attract more beetles to your lawn and the bags become a nasty mess.
Now is the time to look closely at your plants to catch any problems and reduce the amount of damage these insects can do. Although some types of insect infestations are easy to recognize, others require a professional.