- Author: Ben Faber
Implications for tequila growers
Agave are a common sight in Southern California and are frequently used in landscaping for homes, businesses, and in public spaces. You've almost certainly seen agave growing in your neighborhood and may even have some growing yourself. Many varieties of agave are grown in San Diego nurseries to keep pace with the demand for these plants across the state and country. As the climate continues to warm and California becomes increasingly dry, hardy and water-conscious plants like agave will more frequently be used in xeriscaping and as ornamentals. However, there is an almost invisible enemy that threatens many of these agave plants. Greasy streaks and smudges appear on leaves, followed by lesions and plant decline. Sometimes, the entire core of the agave collapses. The plants look sickly and unattractive, dismaying homeowners and nursery growers alike. What is causing this damage? Mites.
Agave mites are a difficult pest to manage and can be a serious problem on multiple types of agave. Being proactive and removing infected plants is currently the best way to protect your agave from mite infestations. Recognizing agave mite symptoms and being ruthless with eliminating plants is key to preventing damage. Research on management options is just beginning and there are still many unknowns, so please contact us if you are having issues with agave mites at your nursery, if you have questions, or if you think there is something we should know about. Stayed tuned for future results and hopefully some better news on how to manage this tiny menace!
- Author: Dustin Blakey
There is a lot of variety in the job of a farm advisor. Some days I'm working with water quality. Other times I answering tree questions. Today I had an insect to identify.
It took a little work, but the insects were banded ash borers.
- obvious yellow stripes
- a slender form
- long antennae
- sturdy legs
- Author: Dustin Blakey
I've noticed as I get older my Christmas wish list gets less interesting and more practical. I have to work harder now to think of fun stuff. Instead I end up with great ideas like silverware. I know I'm not alone.
So what do you get that special someone who insists on a practical gift?
As I was looking for ideas for my wife—a poster child for gifts practical and boring—I discovered that many people give pillows as Christmas gifts. At first I thought that was weird, but then I remembered that last year she gave me a fancy, hypoallergenic, contouring pillow. It's very comfy. Maybe I should return the favor?
This ultimately led me down the Google Search Rabbit Hole where I soon encountered dire warnings about dust mites.
As a county agent in Arkansas, I encountered dust mite complaints a few times a year. Most of the time it was a case of delusory parasitosis, but sometimes it appeared to be a legitimate complaint, especially in wet years when conditions for their growth were favorable.
House dust mites are microscopic mites that feed on dead skin. They may be allergenic or asthma-inducers to some individuals. There is a large amount of scary information about them, but the truth is most people will have little to worry about from house dust mites.
House dust mites thrive in warm, high-humidity environments. Judging from the condition of my skin right now, I'd say that I am located in the polar opposite of a high-humidity environment. Locations that experience seasonal dry spells with low humidity (think: Eastern California) have a hard time maintaining large populations of house dust mites. These mites prefer climates like the Southeast US where the air feels more liquid than gaseous. In California, they are most commonly found along the coast.
In most of the western US, you probably have little to worry about. You would do better focusing on earthquake preparedness instead of these microscopic detritivores. (Google that instead of dust mites if you're bored. It's much more helpful.)
If you are still concerned about house dust mites—because who isn't after reading about them?—there are a few easy measures that will control or avoid the problem with things you already have. Reducing inside humidity below 50% will help. Heaters and air conditioners* both lower relative humidity. Pick whichever seems appropriate.
Frequent vacuuming of suspect furniture, rugs, and fabrics will reduce mite populations by reducing food sources. This is especially helpful for pet owners. Mattresses and pillows can be encased in protective covers if you are one to err on the safe side and have extra money to spend; however, many pillows (or their cases) can be washed. Mattresses can be vacuumed, too. Mites or not, this is just a good way to keep things clean.
You do not need to use any fancy, hi-tech control gimmicks or pesticides you may find on the internet.
All this to say: if you want to get your spouse a new pillow this holiday season, get one based on comfort and be wary of diving too deeply into pointless online searches like I did.
Or you could just play it safe and get some new silverware. Just don't forget to wash it before using.
* Not swamp/evaporative coolers, but you wouldn't be using those in a humid environment anyway.
For more information on house dust mites, consider clicking on these exciting links:
- Author: Anne E Schellman
Last week, someone called our helpline about a strange phenomenon happening on her backyard plants. She described the symptoms as “big, white, masses of fluffy cotton.” I asked her to email some photos our helpline address (ucmgstanislaus@ucanr.edu).
When I opened her email, I was surprised to see images of what appeared to be giant whiteflies. This pest invaded California in the early 1990's and was until recently only found in Southern California and along the coast. The Stanislaus County Agricultural Commissioner's Office confirmed that giant whiteflies are present in our County.
If you've heard of whiteflies or dealt with them in your landscape, you may wonder how giant whiteflies are different, aside from being larger. Both pests suck plant juices and weaken plants. The main difference is that giant whiteflies tend to feed together in large groups. This large population creates waxy looking deposits that create a “bearded appearance” or what the caller described as “fluffy cotton” on plants. If you look closely at the infestation, you may see the pests living on the undersides of the leaves.
If you find giant whiteflies in your landscape, there are a few things you can do. For small infestations, pull off affected leaves, place them in a sealed bag, and discard them. For larger ones, direct a strong stream of water at the undersides of the leaves to knock giant whiteflies off and kill them.
Visit the UC IPM publication Pest Notes: Giant Whitefly for more information about this pest, or call our helpline at (209) 525-6802 to speak with a UCCE Master Gardener.
- Author: Dustin Blakey
I know you'll be glad to hear that there is a new garden pest in the Eastern Sierra. Well, it's native and so not technically new, but as far as I know, gardeners haven't had to deal with it in recent memory.
This insect is a stink bug with the gnarly name of Chlorochroa kanei. Don't try to say it quickly! As far as I know there is no common name for it. Characteristically it has a single dot on its back and a light border around its body. The color, at least this year, has been black, but dark green and brown variants are known to exist.
It normally feeds on the Great Basin plants in the desert, but this year it has shown up in gardens. We have seen it so far on English peas, artichokes and possibly potatoes. I tried to find a preferred host list for this pest and there wasn't really information. Other species of Chlorochroa do have preferred hosts figured out, but not this one.
If you encounter this pest, please let us know in the comments, and tell us which plants you found it on so we can better know what to look for.
Probably the best control in the garden will be to physically remove them and their eggs. UC IPM has some general information about stink bugs online here, but nothing on this particular pest. Information for those other species will apply here as well.
Chances are we may not see it again in the garden, but you never know!