We continue to receive numerous inquiries about bagworms on landscape plants, especially evergreens. Since we’ve addressed this issue several times over the last few years, I won’t take the time to repeat the information here, but you can find the answers to most of your questions from the Purdue Extension entomology specialists online at http://www.ppdl.purdue.edu/PPDL/weeklypics/7-29-02-1.html and http://extension.entm.purdue.edu/publications/E-27.pdf.
Q. I have learned about this dreadful stuff called artillery or shotgun fungus the hard way — namely by having it all over my house. Is there any way to get this stuff off?
A. The artillery or shotgun fungus is aptly named for the characteristic ability to propel its spores a considerable distance. In fact, the scientific name for this fungus is Sphaerobolus, Greek for “sphere thrower.” Artillery fungus is one of nature’s recyclers, growing on decaying organic matter, including the bark mulch commonly used in the home landscape, and is common throughout the United States. This fungus is very tiny, so it mostly goes undetected until it releases its spores with a sticky substance that rivals superglue. The structure that releases the spores is actually sensitive to light, and, thus, aims its sticky spores toward a light source, which might just happen to be the light-colored side of your house or car!
Once these spores are stuck to a surface, they are very difficult to remove without damaging the surface below. The sooner you notice and try to remove the spores, the more likely the success. Power washing, where practical, might do the trick. Otherwise, you can try soaking the area with mild soapy water followed by cautious scraping, but most folks report that this is futile. Diluted bleach solution might also help, but test it in an inconspicuous area first to be certain the surface can tolerate the bleach. To prevent this fungus from continuing to be a problem, remove the bark mulch and replace with gravel, stone, plastic or fabric mulch.
Q. I was wondering if you had any gardening tips on how to keep grass and weeds out of my asparagus. I used to pull it out by hand. But I can’t do that now.
A. Weed control is a constant challenge in the asparagus bed, but the best defense is a healthy stand of asparagus plants, meaning proper fertilizing, watering and scouting for pests and diseases. A vigorously growing asparagus patch can outcompete many of the weeds, especially once you’ve quit harvesting in early summer. So the next most important strategy is early-season weed prevention and control through the harvest season by hand pulling, hoeing and mulching with clean, weed-free mulch. There are pre-emergence herbicides labeled for use in asparagus that can be used to reduce the germination of many annual grasses and broadleaves. But these will not control existing perennial weeds. In established plantings, after the last harvest when no asparagus foliage is above ground, a home garden formulation of glyphosate non-selective herbicide can be carefully applied to any existing weeds. Be sure to read and follow all label directions. Another alternative at this time would be to use a flame weeder, a propane-fueled wand that directs a flame to a small, targeted area. The National Sustainable Agriculture Information Service has an excellent article on flame weeders at https://attra.ncat.org/what-can-you-tell-me-about-flame-weeding-as-a-method-of-weed-control-in-organic-crops-1/. Whether using herbicides or flame weeders, please read and follow all label directions.
Do not use salt as a weed killer. Although it generally will not harm the asparagus, it does inhibit water penetration in the soil. So, over the long term, it does great damage to your soil structure.
More information on weed control in the garden and landscape is available in Purdue Extension Bulletin HO-96, online at https://ag.purdue.edu/hla/pubs/HO/HO-96.pdf.