Laura Jesse, of Iowa State University Extension’s Plant & Insect Diagnostic Clinic, wrote the following about garden slugs:
Slug photo by Laura Jesse of ISU Extension
There seem to be plenty of slugs in my garden, but I hope not in yours. Slugs leave small, irregular holes all over the leaves of plants. They especially seem to like my hostas but they are not picky feeders. Slugs are difficult to detect because they feed only at night. Slugs look like snails without a shell. They vary in size from less than an inch up to 2 inches in length, grayish colored, and a bit slimy to the touch. In fact as they crawl along they leave a slime trail.
Slugs need moisture to survive and are found under mulch, rocks, logs, and other damp locations. My hostas tend to be eaten because they grow in a garden that is shaded and holds the moisture longer.
Reducing slug damage is not an easy task and nothing will fix holes already there, so your first question should be – how bad is this and can I live with the damage? If you do decide to try to reduce the slug population you should combine several tactics. First, remove mulch and reduce moisture from around the base of afflicted plants as much as possible. Remove slugs you find either by using a trap such as a board on the ground that slugs will gather under or pan traps with beer as a bait. I assume cheap beer works fine and would not waste expensive beer on this. Remove dead slugs daily or it will get pretty disgusting. Finally there are commercially available slug baits available containing a molluscicide, but they are best used in the spring or fall.
I spotted the first Japanese beetle of the season yesterday on my raspberry bushes. I went to check one of my rose bushes and sure enough, there was another one, sucking the life out of a beautiful pink bud. Unfortunately, both got away.
The beauty of these copper-colored beetles belies the devastation they wreak. Adult Japanese beetles feed on more than 300 types of plants – turning leaves into lacy skeletons. As larva, the white c-shaped grubs feed on turf grass roots.
I’ve heard some people have luck with the Japanese beetle traps that can be found at garden centers. Others say the traps just lure more beetles into your yard. When I see just a couple of the bugs, I use the squish method, but as they become more numerous, I’ll try to control their numbers with soapy water.
Take a small bucket with water and dish detergent – any kind will probably work – and knock the beetles off the plants into the bucket. The beetles are more active at certain times of day and will fly off. Othertimes, they do a drop and roll, which is the best way to get them to fall into the bucket. Early evening seems to be the time when they are more sluggish and easier to catch that way. Obviously, if you are growing crops that the beetles are attacking, such as grapes (another favorite,) you’re going to need a different method of control. They also favor certain trees, but supposedly they don’t kill the trees as do pests like the emerald ash borer. I also wonder what they will ultimately do to the monarch butterfly population, as Japanese beetles devastate the monarch’s food source, milkweed.
Since they make my top 10 bad bugs list, the Japanese beetle and different control methods can be found in several posts on this blog. Just use the search box at the right to find more from city arborist Daniel Gibbons, master gardeners and others on this foreign invader.
Sunday’s Homegrown Highlights column in the Gazette shows that a) the only thing predictable about March weather is that it’s unpredictable and b) our columns for Sunday’s newspaper are written in advance. Hopefully, no one dug under several inches of snow to begin “waking the garden.”
In fact, the snow acts as insulation for plants from the cold. Ones that have already bloomed might be done for the season after being buried under snow, but those that were just emerging – tulips, daffodils (at least those here in Cedar Rapids that have not blossomed yet) and others should be fine.
I’ve been able to resist the temptation to begin yard work even on those beautiful, sunny and 70-degree days of March, and I will at least for the first couple weeks in April. Until the ground is fairly dry – much less soggy than what it’s been recently – it’s really best to stay off the lawns and out of flower beds. I know a few vegetable gardeners who already planted potatoes and onions before this weekend’s snow. Some vegetables are more tolerant of the cold and can survive even in weather like this. Just remember, there’s no reason to jump the gun on yard work. Enjoy each season as it unfolds. There will be plenty of time for outdoor work in the months to come.