- Author: Denise Godbout-Avant
My first step was to go to the University of California Agricultural and Natural Resources Integrated Pest Management Program (IPM) website to possibly determine what the manzanita plants had. IPM is a wonderful resource with a wide range of links with information on science-based home, garden, turf, and landscape pest management. http://ipm.ucanr.edu/
After doing some exploring on IPM I learned the plants probably had Manzanita leafgall aphid (Tamalia coweni). I knew of galls caused by tiny wasps existing on some trees such as oaks but learning that some aphids can cause galls was new and fascinating knowledge to me!
This website also includes links to the Stanislaus Sprout which is a weekly blog packed with information, upcoming classes and workshops, and gardening publications. https://ucanr.edu/sites/stancountymg/
Managing the Manzanita Pest
One IPM solution given was to avoid frequent irrigation or with excessive amounts of water. Once manzanita plants are well-established, they thrive with less frequent watering, so I was already not watering them often. Pruning was not recommended since it would stimulate new growth, which could attract more aphids, though I did remove leaves with the galls on them.
Take Advantage of These Resources
You do not have to be a Master Gardener to take advantage of the science-based resources I have discussed, the Integrated Pest Management website and the Stanislaus County Master Gardeners' Help Desk. They are available to all, not just to Master Gardeners. Like me, you can continue to learn new information that you can apply to your garden!
Resources and Information
- Aphids: http://ipm.ucanr.edu/PMG/PESTNOTES/pn7404.html
- Beneficial insects, including lady beetle larvae and paper wasps: http://ipm.ucanr.edu/QT/beneficialpredatorscard.html
- Beneficial insects: http://ipm.ucanr.edu/QT/beneficialinsectscard.html
- Oak Galls: (http://ipm.ucanr.edu/PMG/GARDEN/PLANTS/INVERT/oakgallwps.html
Denise has been a Master Gardener since 2020. All photos taken by Denise Godbout-Avant unless otherwise noted./h3>
- Author: Denise Godbout-Avant
Seasonal Landscape IPM Checklist for Home Gardeners
UC's Integrated Pest Management (IPM) Home, Garden, Turf and Landscape Pests Quick Link has a Seasonal Landscape IPM Checklist which is a wonderful resource with monthly checklists within your selected county/region to help guide you how to keep your landscapes healthy.
Topics include common pest problems to look out for, preventative measures, and links to more information. You can also subscribe to receive an automated monthly list by email.
December and January Lists
I reviewed the December and January checklists for Stanislaus County. The following are some topics listed and additional appropriate links:
- Frost – Temperatures sometimes drop to freezing during the winter months. Cold temperature can kill bark, buds, flowers, and shoots, so protect sensitive plants from frost. To increase a soil's ability to absorb heat rake away mulch to expose the ground around the base of the plant. If frost is expected irrigate the soil (if there hasn't been any rain recently) at least three days prior. You can also cover sensitive plants overnight with cloth or similar material other than plastic but leave covers open at the bottom so heat from soil can help warm plants and remove covers during the daytime. http://ipm.ucanr.edu/PMG/GARDEN/ENVIRON/frostdamage.html
- Irrigation – Always adjust your watering schedule according to the weather. We have had a very wet December, which followed an atmospheric river storm in October. So, gardens have needed little to no irrigation lately, depending on your soil type. Overirrigation can lead to root rot. Resume irrigation if storms diminish during the remainder of the winter (let's hope it remains wet!). If there is an extended dry spell during upcoming winter months, irrigate infrequently and deeply. http://ipm.ucanr.edu/homegarden/irrigating/
- Clean up – Remove old fruit and nuts in and under trees to avoid harboring pests. Also rake up fallen leaves beneath deciduous fruit trees and roses (but leave the leaves elsewhere in your yard for beneficial overwintering insects including butterflies and bees). http://ipm.ucanr.edu/PMG/GARDEN/FRUIT/CULTURAL/sanitation.html
- Prune – Trees and shrubs that need pruning including apple, crepe myrtle, pear, rose, spirea, and stone fruits (exception are apricot and cherry trees which can harbor certain pests, i.e. shothole borer, which should be pruned in the summer). Remove dead and diseased wood. http://ipm.ucanr.edu/homegarden/pruning/
- Mistletoe – Mistletoes are parasitic plants that absorb nutrients and water from a host tree. Healthy trees can tolerate a few branches infected with mistletoe, but a heavy infestation could ultimately kill a tree, particularly if the tree is stressed or unhealthy. With leaves having dropped during fall months from deciduous trees, mistletoe is visible on the now-bare trees, and thus can be removed easily. Remove branches at least a foot below the mistletoe attachment before it produces seeds that will infest other limbs and trees. Since mistletoe often infects many trees on the same street, a neighborhood effort to remove all mistletoe from any trees on the block will help reduce continued spread in the area. http://ipm.ucanr.edu/QT/mistletoecard.html
- Peach leaf curl –If leaf curl has been an issue on your peach or nectarine plants apply preventive spray once or more times until bud break. http://ipm.ucanr.edu/QT/peachleafcurlcard.html
- Bare root plants – Now is the time to plant bare root deciduous trees, shrubs, and vines, including roses, fruit, nuts and grapes. Select species and cultivars that are appropriate for the site it is being planted. http://ipm.ucanr.edu/homegarden/planting/
This compilation is a partial overview of the lists I reviewed. Check out the January seasonal landscape checklist for your area to see which tasks you need to do. Then bundle up, get your garden tools, and go outside (preferably on a sunny day!) to do the necessary winter maintenance chores in your garden. You and your landscape will be rewarded for your cold weather efforts come spring.
Denise Godbout-Avant has been a UCCE Stanislaus County Master Gardener since July 2020./h3>
Take our Pest Management in Vegetable Gardens class to learn how to identify pests and manage them using less toxic solutions. You'll also learn how to recognize beneficial insects, too.
Where: On Zoom. You will receive a link the morning of the class.
When: Tuesday, May 18, 2021 6:00-7:30 p.m.
Register at: http://ucanr.edu/vegpests/2021
Instructors: Rho Yare & Anne Schellman
Planting for Pollinators will focus on native and compatible non-native plants that thrive in our area, and which pollinators have been documented visiting these plants.
It can sometimes be hard to spot these pollinators, so our speaker will tell us what time of year to look for them, and which plants to use to attract them.
Watch our YouTube Video at https://www.youtube.com/watch?v=naL3BM5aP-s&t=5s
About the speaker:
Ellen is a professional Horticulturist specializing in beautiful, heat tolerant, reduced-irrigation plantings that thrive in landscapes in the Central Valley of California. Most recently she has been exploring her passion for Pollinator Gardening and how it can contribute to biological diversity in urban and suburban California landscapes.
- Author: Denise Godbout-Avant
According to UC Integrated Pest Management (UC IPM), aphids are small, soft pear-shaped bodied insects with long legs and antennae, with slender mouthparts used to pierce stems, leaves and other tender plant parts to suck out plant fluids. The site recommends first attempting to control aphids by washing them off with a gentle stream of water. I did this over several mornings and evenings, with my hose set on fine spray, washing both the top and underside of the leaves. After about a week, I still had quite a few aphids, so I sprayed an insecticidal soap, making sure I covered both the top and bottom of leaves. Aphids produce many offspring, so they required an additional treatment.
Soft scale is a sucking insect, appearing as tiny dots on the leaves or stems of a plant. They can grow up to ¼ inch long and have a smooth, cottony or waxy surface. They feed on the sap of the plant and excrete sticky honeydew, which can attract ants. Mine were brownish-yellow with a waxy color, usually appearing on the underside of the leaves.
I removed badly damaged leaves, checked undersides of the leaves for the scale and scraped off any scale I found using a wet Q-tip. I also checked my other two plants and occasionally found a scale or two on them, scraping them off also. I repotted the infested plant with potting mix. Over time I was able to completely get rid of the soft scale.
My Buggy Summer Summary
It has been an educational summer learning about these insect pests and dealing with their infestations. I'm gratified I've been able to manage them using less toxic pesticides that are less harmful to beneficial insects and the environment. You can learn more about less toxic pesticides such as insecticidal soaps and oils by visiting the UC IPM website or by watching this video.
Denise is a UCCE Stanislaus County Master Gardener.