Advice for the Home Gardener from the Help Desk of the
UC Master Gardener Program of Contra Costa County
MGCC's Help Desk Response: Thank you for contacting the UC Master Gardener Program Help Desk with a question about your elm tree. Thanks also for sending good photos of the leaves, and especially of the insect. The insect is an elm leaf beetle, and it chews small round holes in elm leaves. A heavy infestation of the beetles can actually defoliate a tree, and multiple years of this will weaken the tree and cause its decline.
Managing elm leaf beetles will require an integrated program that includes good cultural care, conservation of natural enemies, regular monitoring, and possibly insecticides and bark banding by a licensed tree care company.
Cultural care: Elm trees are native to areas with summer rainfall, so you will need to give them adequate irrigation during our dry months. Pruning should be done just to remove dead branches. Avoid unnecessary pruning.
Preserving natural predators: Predators of elm leaf beetles include earwigs, lacewing larvae, some ground beetles and several others. To preserve these in your landscape, minimize pesticide application on surrounding areas and use less-persistent products, or apply pesticides in a band on the trunk (this will kill larvae when they crawl down the tree to pupate, thus reducing next year's problem). Bark banding, while it can be effective, may require application by a licensed pest control operator because the chemicals are not available for home use. Short-lived contact sprays of oils such as Neem oil or horticultural oil, or Spinosad can work, but only if the tree can be thoroughly sprayed, which is unlikely in a tree as large as yours.
Systemic insecticides can also be used for control of elm leaf beetles. These are applied to one area of the tree (bark, roots, etc.) and are moved to other parts of the tree (leaves). These pesticides when injected into the tree, or into the soil, minimize environmental contamination. Because elms flower before leaves come out, and are wind pollinated, the risk of harming beneficial pollinator insects is low when using a systemic insecticide on elms.
This link will take you to more information about elm leaf beetles: http://ipm.ucanr.edu/PMG/PESTNOTES/pn7403.html.
There are other things that can cause problems for elm trees. The dead and dying branches at the top of the tree may be from a lack of water, but could be from a disease such as verticillium wilt which typically shows with dying branches at the top of the tree. Keeping your tree happy with adequate irrigation is probably the best thing you can do. For more information on elm tree pests and diseases see: http://ipm.ucanr.edu/PMG/GARDEN/PLANTS/elm.html.
I don't know specifically how large your tree is (e.g., width), but it can take up to 200 gallons of water a week appropriately applied to keep a large elm healthy. Elms are listed as needing moderate water (in a range of very low to high). To calculate how much water you should be applying each month, go to this website: http://www.waterwonk.us/how-much/ where you can input the size of the tree (and that is how wide do the branches spread tip-to-tip) and the month. It will calculate the amount of water needed for optimal care.
Please let us know if you have more questions.
Good luck!
Help Desk of the UC Master Gardener Program of Contra Costa County (SEH)
Note: The UC Master Gardeners Program of Contra Costa's Help Desk is available year-round to answer our gardening questions. Except for a few holidays, we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 75 Santa Barbara Road, 2d Floor, Pleasant Hill, CA 94523, although we will be moving this spring. We will notify you if/when that occurs. We can also be reached via telephone: (925)646-6586, email: ccmg@ucanr.edu, or on the web at http://ccmg.ucanr.edu/Ask_Us/ MGCC Blogs can be found at http://ccmg.ucanr.edu/HortCoCo/ You can also subscribe to the Blog (http://ucanr.edu/blogs/CCMGBlog/)
Help for the Home Gardener from the Help Desk of the
UC Master Gardeners Program of Contra Costa County
Client's Request: Thank you for contacting the UC Master Gardener's Help Desk. I researched the problem as you described it to me via phone, i.e., that there are numerous holes in your lawn that are not gopher tunnels but something else, some other kind of animal perhaps.
MGCC Help Desk Response: I reviewed other call-ins that may have a similar problem and also researched the UC ANR Pest Notes for likely causes. Numerous holes in the lawn are usually signs that animals are digging for grubs or insects living in or just below the turf. It is common for Raccoons, Opossums, and Skunks to forage in this manner.
You may test your lawn for the presence of these subsurface pests with a simple soak test. Mix 2 Tablespoons of dish soap with 2 Gallons of water and soak one area 3' x 3'. The mixture will cause insects to move to the surface and you can identify and count those that emerge. You can use the IPM website to identify the insects or grubs and learn what to specifically apply to control the pests at http://ipm.ucanr.edu/QT/lawninsectscard.html. Even more detailed information on controlling pest in your lawn can be found at http://ipm.ucanr.edu/TOOLS/TURF/.
Whether you have Raccoons, Opossums, or Skunks, there are some measures that can be taken to make your lawn less attractive to them, such as removing any wood piles, scrap piles, pet food, and fallen fruit. Screening off ground access under porches and decks and other areas they can use as habitat. The pest note page at http://ipm.ucanr.edu/TOOLS/TURF/PESTS/vertrac.html will show you how to identify and mitigate these problems.
Hopefully, this has been helpful in getting you started on finding the source and fixing the problem. Should you need more input, contact us by phone or email at the contacts listed below.
Help Desk of the UC Master Gardener Program of Contra Costa County
Note: The UC Master Gardeners Program of Contra Costa's Help Desk is available year-round to answer your gardening questions. Except for a few holidays, we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 75 Santa Barbara Road, 2d Floor, Pleasant Hill, CA 94523. We can also be reached via telephone: (925)646-6586, email: ccmg@ucanr.edu, or on the web at http://ccmg.ucanr.edu/Ask_Us/ MGCC Blogs can be found at http://ccmg.ucanr.edu/HortCoCo/ You can also subscribe to the Blog (http://ucanr.edu/blogs/CCMGBlog/).
Help for the Home Gardener from the Help Desk of the
UC Master Gardener Program of Contra Costa County
Help Desk Response: Thank you for contacting the UC Master Gardener Program Help Desk with your request for advice and tips on eliminating voles in your garden landscape.
Voles, also known as meadow mice, can be quite prevalent in home gardens. They have above-ground tunnels or pathways through vegetation, as well as underground tunnels. Entrances to their tunnels are small (1 1/2 to 2 inches) and are left open, not plugged. There may be many open tunnels within a small area. Voles are active both day and night, and emerge from their holes to forage for food.
Voles can cause damage to plants in your yard, as you've already experienced. They eat grasses and many landscape and vegetable plants, and can also damage trees by eating the bark. If trees lose their bark all the way around the trunk, it can kill the trees. So it is worthwhile to begin eliminating the voles now, before they do too much damage.
It is important to modify the habitat in your yard so that the voles do not have places to hide from predators. Keep your lawn mowed short to prevent them from forming above ground tunnels in the grass. If possible, mow or remove other nearby ground covers such as ivy. Voles don't like to be exposed on open ground where predators can attack them.
When the vole population is concentrated in a small area, trapping can be effective. For a small garden, consider using using at least 12 traps. You can use a simple, wooden mouse trap baited with a peanut butter-oatmeal mixture or apple slices. Place the traps near the tunnel entrances with the trigger end and bait near the opening. Check the traps daily and keep setting new traps until you no longer find them triggered. Use gloves when removing the voles from the traps, and either bury them or bag them and discard in the trash.
Once the voles are gone, destroy their tunnels by digging. This will discourage others from repopulating the tunnels from outside your yard. Additional specific information about managing voles can be found at this University of California website:
http://ipm.ucanr.edu/PMG/PESTNOTES/pn7439.html
If you have fruit trees or other prized trees, you can protect their trunks with plastic cylinder barriers as shown and described in the link above, or with metal roof flashing. Voles are not skilled at climbing, so the barrier does not need to be higher than 12 inches.
We hope that this information will help you to control your vole population. Please let us know if you need additional information.
Help Desk of the UC Master Gardener Program of Contra Costa County (SLH)
Note: The UC Master Gardeners Program of Contra Costa's Help Desk is available year-round to answer your gardening questions. Except for a few holidays, we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 75 Santa Barbara Road, 2d Floor, Pleasant Hill, CA 94523. We can also be reached via telephone: (925)646-6586, email: ccmg@ucanr.edu, or on the web at http://ccmg.ucanr.edu/Ask_Us/ MGCC Blogs can be found at http://ccmg.ucanr.edu/HortCoCo/ You can also subscribe to the Blog (http://ucanr.edu/blogs/CCMGBlog/).
Advice for the Home Gardener from the Help Desk of the
UC Master Gardener Program of Contra Costa County
Client: Help!!! I'm a relatively new vegetable gardener. I just planted my summer vegetable garden seedlings this week. Within the week I'm finding severely damaged zucchini seedlings with holes in the leaves and for some of them the entire seedling is gone. What is doing this? And what can I do to prevent such damage?
Control of these pests in the garden is usually a combination of methods. Hand picking at night with a flash light can be a quick and easy way to control the population. As you pick them off your plants or off the ground you can drop them into a container of mild soapy water. I personally like to wear garden gloves for this task. The water can be drained off in an out of the way spot in your yard and the snails and slugs disposed of in your trash bin.
The fourth possibility is birds. Pesky birds can do a lot of damage to your tender young plants. However, they are also your "friend" for all the garden pests they feed on as well as being protected by law. If birds are the "problem", to control the birds you will need to get some "bird netting" over your plants. Half-inch diameter PVC pipe works well for making an arch or tent over your plants. The method would be to drive 24" pieces of ¼ inch re-bar into the ground about 2 to 3 feet apart along BOTH sides of your plants (and opposite one another) far enough apart so that the PVC can be readily bent into an arch and slide over both of the opposite re-bars,. Stretch your bird netting over the arches and secure it in place with clips, string or twist-ties. You can also find some other methods of making these arches on YouTube videos at https://www.youtube.com/watch?v=vEn-XQ5nA4k
Free UC Guidance on Snail & slug Management in the garden
(includes videos on identification of pest, applying bait, etc.):
http://ipm.ucanr.edu/PMG/PESTNOTES/pn7427.html
Free UC Guidance on Earwig Management in the garden:
http://ipm.ucanr.edu/PMG/PESTNOTES/pn74102.html
I would do the nighttime check for snails and slugs first and try some of the trapping methods before I went to the trouble and expense of putting up bird netting. With a little effort I believe you can get the problem under control. However, the sad news is it looks to me like the zucchini plant will need to be pulled out and replanted as there does not seem to be enough leaf material left to sustain the plant. There is some good news here though, it's early in the growing season and the new zucchini will catch up in no time.
Help Desk of the UC Master Gardener Program of ContraCostaCountyf (BHD)
Note: The UC Master Gardeners Program of Contra Costa's Help Desk is available year-round to answer your gardening questions. Except for a few holidays, we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 75 Santa Barbara Road, 2d Floor, Pleasant Hill, CA 94523. We can also be reached via telephone: (925) 646-6586, email: ccmg@ucanr.edu, or on the web at http://ccmg.ucanr.edu/Ask_Us/ MGCC Blogs can be found at http://ccmg.ucanr.edu/HortCoCo/ You can also subscribe to the Blog (http://ucanr.edu/blogs/CCMGBlog/).
UC Master Gardener Program of Contra Costa
Client's Request: My coworker brought me some red onion seeds from Mexico. I have a small garden bed in my backyard and wanted to get some general info. on planting them. Some of the questions I had were: -How deep should I plant the seeds? -how far apart? how often should I water them? and what nutrients do they need to thrive?
UCMGCC Help Desk Response: Thank you for contacting the UC Master Gardener Help Desk with your question about onion seed from Mexico.
Please help protect California agriculture by not importing foreign pests or diseases!!
If the seeds did go through inspection at the border and were Ok'd for entry, then it would be Ok to use them.
Onion seed should be planted 1/4 inch deep. Plants should be 4 - 5 inches apart - you can plant the seed more closely and then thin to the proper distance once you see which seedlings are the strongest. You may also be able to eat the “thinnings”.
If you live in west county, plant between January and September. If you live in a warmer part of the county, plant between February and October.
Keep the soil moist until the plants have emerged and look sturdy. Onion is a high water needs plant. Additional information on watering and harvesting can be found here http://ipm.ucanr.edu/PMG/GARDEN/VEGES/CULTURAL/onionwatering.html
Fertilizer needs depend upon the quality of your soil. You should test your soil for the 3 main nutrients: nitrogen, potassium and phosphorus. You should also do a pH test, since if pH is high, micronutrients may not be available to the plants. Relatively inexpensive soil test kits can be purchased at garden centers. Or, if you prefer, you can send a soil sample to be analyzed by a commercial laboratory. A suggested list of laboratories can be found at http://ccmg.ucanr.edu/files/51308.pdf. You'll want to visit their websites to learn how to take and submit samples, and what the service will cost. Once you know the condition of your soil, you can determine what nutrients would need to be added, if any. If you needed further advice about fertilizing once you have your soil test results, feel free to contact us again. Additional information on fertilizing can be found here: http://ipm.ucanr.edu/PMG/GARDEN/VEGES/CULTURAL/vegefertilizing.html.
More information about growing onions can also be found at this University of California website: http://ipm.ucanr.edu/PMG/GARDEN/VEGES/onions.html.
I hope that this information is helpful and you get some great onions.
Help Desk of the UC Master Gardener Program of Contra Costa County (JL)
Note: The UC Master Gardeners Program of Contra Costa's Help Desk is available year-round to answer your gardening questions. Except for a few holidays, we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 75 Santa Barbara Road, 2d Floor, Pleasant Hill, CA 94523. We can also be reached via telephone: (925) 646-6586, email: ccmg@ucanr.edu, or on the web at http://ccmg.ucanr.edu/Ask_Us/ MGCC Blogs can be found at http://ccmg.ucanr.edu/HortCoCo/ You can also subscribe to the Blog (http://ucanr.edu/blogs/CCMGBlog/).
