I have been getting some questions and various topics over the past couple weeks so I thought I would take this week to address those with a broader audience.
Remember you can still email your questions to me at email@example.com.
Question: You mentioned that the periodical cicadas we are seeing may damage our plants. Is this something that should concern us?
Answer: For the most part, the damage is not a real problem. It is mostly cosmetic. The cicadas are emerging for their 17-year cycle. They will mate, the females will lay eggs then the adults will die. The eggs hatch after about 6 weeks and the young larvae drop to the ground where they burrow in and live for the next 17 years. The adults will be around for about four to six weeks. After mating, the female will lay her eggs in the new growth on trees and woody shrubs. She does this by cutting a 1 to 2 inch long slit on the twig. Because of this egg-laying method, the branch tips will turn brown; this is called flagging. Often, the whole tree is covered with brown branch tips. But do not worry, the tree will grow out of this and fully recover. This process can interrupt the production of fruit on some trees and it may temporarily harm the appearance of some woody landscape plants but the key word is temporary. Treating with insecticide may be a waste of money as more cicadas will fly in to replace the ones you kill. It is best to just sit back and enjoy their song, you won’t hear it again for 17 years.
Question: Should I be concerned about this new “Murder Hornet” I keep hearing about on the news?
Answer: At this time, no. The more proper name for this beast is Giant Asian Hornet (Vespa mandarinia). So far there have only been four found in Canadian British Columbia and only two found in the state of Washington. It is possible that, if a population of these hornets gets established, they may eventually find their way here several years from now. But, there is no indication at the present time that they have established hives anywhere in North America. Those probably came in on shipping containers from an Asian country. The hornets are huge; much larger than anything we have around here.
The concern for these insects is twofold. They are about 2 inches or more in length and their size means they carry a very large sac of venom to supply their stinger. They inflict a painful sting with venom that can dissolve a small amount of body tissue. Just like with other stinging insects, those who are allergic to them can end up in a hospital or worse.
The other concern is with honeybees, their preferred food. These hornets will eat a variety of other insects, but when they find a hive of honeybees they will kill the bees and carry their bodies back to the hornet hive to feed the young and the queens. A couple dozen of these hornets can eliminate a honeybee hive in a matter of hours.
But keep in mind, only a couple have been found on the far side of this continent so far. We have a good chance of stopping this problem before it gets started.
Question: I have planted my garden and put down mulch, but now I have weeds coming up. Is there anything I can spray to kill the weeds that won’t hurt the other plants?
Answer: Short answer is no. Most weeds are broad-leaved plants and most bedding plants and vegetables are also broad-leaved plants. Herbicides designed to kill broadleaved weeds don’t know one plant from another, so they will also kill the more desirable plants.
There are pre-emergent herbicides — you may have used a crabgrass preventer back in March — they kill the seeds when they germinate but cause little damage to established plants. Most of these are not labeled to use on food plants such as vegetables as they are too dangerous to eat. They may be used on other plants, but they will often cause some burning on the foliage or stunting.
The best thing to do with an established garden is to just pull the weeds out by their roots.
This will keep you pretty busy in the next few weeks as things start to grow but will fall back to a twice weekly task by late June. You can also take up the mulch and lay down some newspaper or weed barrier around the plants then put the mulch back on top of the paper or barrier, this will give good weed control for the rest of the summer.
I hope everyone is doing well staying at home during the virus outbreak. I am glad we don’t have it as bad here as they have in other areas. Keep washing your hands and wearing those face masks.
Enjoy your garden.
For questions or to suggest a topic for this column, email firstname.lastname@example.org.