Bugs

from page 18 in stores.

“While the traps do capture a large number of beetles, they will attract a greater number than they trap,” she said. “In the end, traps cause more harm than good.”

For those property owners dealing with an overwhelming number of beetles, she said chemical controls are possible depending on the plants they’re feasting on and the size of those plants. More specifics can be found at: https://extension.umn.edu/ yard-and-garden-insects/japanese-beetles.

Ground trouble

The flying, plant-eating beetles begin in the ground as larvae that feed on the root systems of grass or turf. In the soil, they appear as white grubs.

The adult beetles emerge in late June and lay eggs in the turf during July.

“The eggs hatch in two to three weeks and tiny white grub larvae begin to eat the grass roots,” Drewitz said. “The grubs grow rapidly and are fully grown by late August or September.”

The feeding on the root system causes the grass to wilt and fade. If extreme grub populations are present (10 or more white grubs per foot), they will cause the grass to die. The damage is usually most apparent from mid-August on and can be localized in specific spots.

At first glance, the grass may appear stressed from drought with a gray-green discoloration. In places with the most severe damage, the grass can be rolled back like a “loose carpet.”

Though grubs may go unnoticed by humans, racoons, skunks and crows will find them and often tear up a yard as they peck out their prey.

Because adult beetles emerge in late June and lay eggs in July and the larvae are fully grown by fall, the first chance to break the cycle is from late May to early August. A preventative insecticide can be applied and watered in. After mid-August and in the springtime when the grubs are fully grown, preventative insecticides are not effective. From August on, a fast-acting, short-lived curative insecticide can be applied to reduce the number of white grubs, but it’s not as effective as a preventative.

Slugs

Springtime can also mean the re-emergence of slugs.

These slimy creatures like cool, damp and shaded places and feed on a variety of plants.

To get these under control, Drewitz recommends hand-treating them. “Consider altering the garden environment by removing the over-wintering leaf mulch, and pruning some plants to create more sun and air movement,” she said.

Bugs from page 19

Additionally, watering plants in the morning helps the area dry out before slugs become most active at night.

She also recommends plantings that slugs don’t like as much:

For full shade (6+ hours of shade):

Perennials: Creeping phlox (Phlox stolonifera), Woodland Phlox (Phlox divaricata), Bleeding Heart (Dicentra)

Ferns

Ornamental grasses: Tufted Hairgrass (Deschampsia), Hakone Grass (Hakonechloa)

Sedges: Grey’s Sedge (Carex grayi), Pennsylvania Sedge (C. pensylvanica), Japanese Sedge (C. morrowii), Plantain Sedge (C. plantaginea)

For light to part shade (3-4 hrs, dappled sunlight):

Perennials: Monkshood (Aconitum), Lady’s Mantle (Alchemilla), Columbine (Aquilegia), Swamp Milkweed (Ascelpias incarnate), False Spirea (Astilbe), Turtlehead (Chelone), Bugbane / Snakeroot (Actaea), Pinks (Dianthus), Spurge (Euphorbia), Cranesbill (Geranium), Coral Bells (Heuchera), Catmint (Nepeta), Evening Primrose / Sundrops (Oenothera), Spiderwort (Tradescantia)

Ornamental Grasses: Oatgrass (Helictotrichon), Reedgrass (Calamagrostis), Blue Fescue (Festuca glauca)

Sedges: Blue Sedge (Carex flacca), Palm Sedge (Carex muskingumensis)

Clematis: Grow this flowering vine on a trellis or fence in full sun, but with the base of the plant shaded and cool.

More information on slugs can be found here: https://extension.umn.edu/yard-and-garden-insects/slugs.