- (Focus Area) Food
Client's Request: I'm a trapper in the Ag Department. We have been looking for plum bud gall mites in the county. I recently came across this plum tree with a huge growth or gall, it's 8" long and 7" wide on the underside of a branch, the tree is around 15 years old. Homeowner wants to know what it is and what should be done about it. The tree is in Pittsburg. Any ideas?
MGCC Help Desk Response: Thank you for contacting the UC Master Gardener Program Help Desk with your question about a very large gall on this 15 year old plum tree in Pittsburg.
I believe this is a gall caused by the bacterium Agrobacterium tumefaciens commonly referred to as crown gall mite or possibly Plum Bud Gall Mite (Acalitus phloeocoptes (Nalepa)). Crown gall, as its name implies, typically appears at the crown of a plant, where the trunk enters the soil but it also can infect the main trunk and side branches. Plum trees are among a long list of plants commonly infected by crown gall including many popular home garden fruit trees (pluots, etc.).
The surface of crown galls and wood underneath is the same color as healthy bark and wood. However, when cut with a knife, crown galls are softer than normal wood and lack the typical pattern of annual growth rings. Galls can be tiny and smooth on young plants but usually are rough and sometimes massive on older trees.
Crown gall appears to have a relatively minor effect on most older plants which is the situation you found. Since this tree is 15 years old and the gall appears to encompass a major part of the main branch I would suggest leaving it be. If the distal portion of the branch starts to decline then the branch can be removed back towards the trunk thereby removing the gall.
Without further inspection of the gall here in our office, another possibility is the Plum Bud Gall Mite (Acalitus phloeocoptes (Nalepa)) which are well described in the Santa Clara County UCCE link below.
Following is a link to a UC Integrated Pest Management website that explains crown gall http://ipm.ucanr.edu/PMG/GARDEN/PLANTS/DISEASES/crowngall.html
and here is a Santa Clara County UCCE link to Plum Bud Gall Mite:
http://mgsantaclara.ucanr.edu/files/300211.pdf
We could give a more conclusive response if you would bring a sample to our offices during our office hours described at the bottom of this response.
I hope your homeowner will be relieved. Good luck.
Help Desk of the UC Master Gardener Program of Contra Costa County (EDC)
Notes: Contra Costa MG's Help Desk is available almost year-round to answer your gardening questions. Except for a few holidays (e.g., last 2 weeks December), we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 2380 Bisso Lane, Concord, CA 94520. We can also be reached via telephone: (925) 608-6683, email: ccmg@ucanr.edu, or on the web at http://ccmg.ucanr.edu/Ask_Us/. MGCC Blogs can be found at http://ccmg.edu/HortCoCo/ You can also subscribe to the Biog.
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 Help Desk with your question about the large bugs on your pomegranate tree. You're right, they are leaf-footed bugs. Your photos are helpful and show adults on your pomegranate fruit.
The following website has useful information about these bugs and how to manage them:
http://ipm.ucanr.edu/PMG/PESTNOTES/pn74168.html
The adults can cause small blemishes on the surface of the pomegranates, with brown spots inside the fruit. The adults are common now because the fruits are getting close to harvest time. As noted in the website, insecticides are usually not warranted but they can be used if an infestation is particularly severe. If your infestation reaches a level at which you conclude you need to apply an insecticide, you'll find recommendations about the type of insecticide to use and when to apply it in the attached document. You will want to be cautious about the use of insecticides if you want to consume the fruit. If you do apply a pesticide, make sure that you follow the instructions on the label regarding the time period to wait between applying the pesticide and harvesting the fruit. Also, wash the fruit before eating it. Additionally, keep in mind that spraying with insecticides may be harmful to bees and other beneficial insects.
Control of the bugs using more physical measures may be helpful. You can get the nymphs and adults out of the tree by shaking the branches or by using a stream of water from the nozzle on the hose. You can squash the bugs once they are on the ground. Because some adults may fly away, you'll want to repeat this process every week or so. You may also be able to pick the bugs off the plants by hand and crush them, wearing gloves to avoid the odor of the bugs.
As you'll see on the website, the adult leaf-footed bugs can overwinter and then re-emerge in the spring to lay eggs. Each adult female can lay up to 200 eggs over a two-month period in the spring. Given this life cycle trait, a good management approach is to try to eliminate places where the insects can overwinter. In your fall cleanup, you will want to remove all the fruit from the tree and clean up debris below the tree to help remove overwintering populations. The adults also overwinter under woodpiles so if you maintain a woodpile you might want to inspect it carefully to remove any of the insects you can locate. In the springtime, the adults feed on weedy plants, so eliminating or mowing woody plants in the vicinity of your pomegranates can also be a good strategy for reducing populations.
Good luck with you pomegranate tree.
Help Desk of the UC Master Gardener Program of Contra Costa County (SMT)
Note:s Contra Costa MG's Help Desk is available almost year-round to answer your gardening questions. Except for a few holidays (e.g., last 2 weeks December), we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 2380 Bisso Lane, Concord, CA 94520. We can also be reached via telephone: (925) 608-6683, email: ccmg@ucanr.edu, or on the web at http://ccmg.ucanr.edu/Ask_Us/. MGCC Blogs can be found at http://ccmg.ignore.edu/HortCoCo/ You can also subscribe to the Biog.
Advice for the Home Gardener from the Help Desk of the
UC Master Gardener Program of Contra Costa County
Help Desk Request: I'm delighted you're available to help diagnose garden problems! Below are four pictures of a grape leaf problem. I have four old vines - Flame and Thompson seedless - that grow against a south-facing solid fence. The vines are close enough that they are co-mingled across the fence. The problem currently is located in one area of the vines and was not visually noticeable three weeks ago. All the vines are vigorous and seem healthy except for the affected leaves. I have cut most of the leaves and vines that are visibly distressed and placed them in my green waste bin. In the 15+ years I've had the grapes I have never had this problem; however, this year I was VERY, VERY late in pruning back the vines, and did not complete the pruning until the new vines had grown a couple feet long. Perhaps the evil villain over-wintered because of my tardy pruning?
Any idea what the problem is - fungus, bug or insect critter, bacteria? I have not seen anything crawling on either side of the leaves. And, what is your recommended approach and treatment? Thanks in advance for your help!
Submitted Representative Images of Affected Grape Leaves (below)
MGCC Help Desk Response: Thank you for contacting the UC Master Gardener Help Desk with your issue of ‘bumps and holes' on your grape leaves.
Thank you for the pictures and note that the blister is on the top of the leaf and the bottom shows fuzzy white. We were able to diagnose simply from the damage itself. The bumps are the result of mites – specifically grape erineum mites. The good news here is that even though the mites infest the leaves, no management is necessary as they rarely lead to any crop losses.
Erinium mites are wormlike, light yellowish white and microscope so you really would need magnification to see the actual mites themselves.
Young leaves show bright pinkish or reddish swellings on upper surfaces. Corresponding areas on lower surfaces are concave and densely lined with a felty mass of plant hairs
The mites overwinter under outer bud scales and move to unfolding leaves in spring. They associate in small groups to feed on lower leaf surfaces; the result is production of masses of enlarged leaf hairs inside a blisterlike area on the leaf. On the undersides of the leaves, beneath the swellings, are concave, densely lined, felty masses of oversized leaf hairs in which the mite populations develop. As the population increases, some move to new areas or to other leaves. From mid-August to leaf drop, there is a movement back to the overwintering site underneath the bud scales.
You indicated that this is new to you and that you were a bit late pruning. I cannot explain for sure why this year and not prior years and I cannot be sure the late pruning added to this situation.
Following is a link to a UC Pest Management website on the subject but it does not really add to the information I have provided above. http://ipm.ucanr.edu/PMG/GARDEN/FRUIT/PESTS/grerineummte.html
Good luck and enjoy those grapes, and do not hesitate to contact us again with garden problems.
Help Desk of the UC Master Gardener Program of Contra Costa County (EDC)
Note: UC Master Gardeners Program of Contra Costa's Help Desk is available almost year-round to answer your gardening questions. Except for a few holidays (e.g., last 2 weeks December), we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 2380 Bisso Lane, Concord, CA 94520. We can also be reached via telephone: (925) 608-6683, 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 Biog.
Advice for the Home Gardener from the Help Desk of the
UC Master Gardener Program of Contra Costa County
MGCC Help Desk Request: What's going on with my persimmon tree? I worked a bunch of compost into the soil around it in the spring and mulched with leaves. But it looks like it needs nutrients. What should I give it? This is its third year since planting. Thanks
Persimmons are generally disease free, but the black spots showing on some of the leaves look like fungal spots. I can't tell from the photo what type of fungus, but there are several that can occasionally affect persimmons. A wet spring, such as we have had, may exacerbate this, as can overhead watering, so you should make sure any nearby sprinklers do not hit the tree. UC does not recommend any treatment other than good cultural care. Removing any fallen leaves also will help. http://ipm.ucanr.edu/PMG/GARDEN/PLANTS/DISEASES/leafspotdis.html.
As long as the spotted leaves are green, I think it would be best to leave them on the tree, as the foliage looks a little sparse - those leaves are still making food for the tree. Now we have hotter and dry weather, leaf spot fungi will be less active.
As you mention, the tree does look like it could use a little help. Persimmons don't generally need a lot of fertilizer, but yours may benefit from a balanced fertilizer for fruit trees (follow package directions ). Make sure the mulch does not cover the bottom of the trunk just above the roots - this area should be clear so that air can get to the roots. When adding compost to the tree you do not need to work it into the soil, which may risk damaging the roots. Worms and other soil creatures will take care of incorporating the compost. Persimmons don't need as much water as some other fruit trees, however, a young tree needs regular irrigation until established, and will do better later on with continued irrigation. The soil should not be overly wet, but do not let it dry out.
The following links give more information about caring for persimmons.
http://www.crfg.org/pubs/ff/persimmon.html
and
http://sonomamg.ucanr.edu/The_Kitchen_Garden/FRUITS/Persimmon/
I hope this information will help your tree to do better, and if you have any further questions, please do not hesitate to contact us.
Help Desk of the UC Master Gardener Program of Contra Costa County (SMW)
Note: UC Master Gardeners Program of Contra Costa's Help Desk is available almost year-round to answer your gardening questions. Except for a few holidays (e.g., last 2 weeks December), we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 2380 Bisso Lane, Concord, CA 94520. We can also be reached via telephone: (925) 608-6683, 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 Biog.
Advice 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.
You sent a photo of a plant for us to identify. It is rosemary (Rosmarinus officinalis). While it's not native to California (it originated in the Mediterranean area), it is very well adapted to California's similar Mediterranean climate. Its flowers range in color from various shades of blue to even pink and white. Its growth habit ranges from stiff and erect, rounded, or low and creeping, depending on variety or cultivar.
This plant is also the rosemary used for seasoning food, however some varieties taste better than others. Bees are attracted to the flowers and make excellent honey when feeding on them.
Good drainage and full sun are essential for a healthy rosemary plant. The links following will take you to more information about growing rosemary: http://ipm.ucanr.edu/PMG/GARDEN/PLANTS/rosemary.html and http://sonomamg.ucanr.edu/Plant_of_the_Month/Rosemary/.
Happy gardening!
Help Desk of the UC Master Gardener Program of Contra Costa County (SEH)
Note: UC Master Gardeners Program of Contra Costa's Help Desk is available almost year-round to answer your gardening questions. Except for a few holidays (e.g., last 2 weeks December), we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 2380 Bisso Lane, Concord, CA 94520. We can also be reached via telephone: (925) 608-6683, 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.