Brent McGhie, Butte County Master Gardener, February 3, 2017.
Western flower thrips are tiny insects. Adults are only 0.8 – 1.4 mm long. They range in color from dark brown in the spring to a lighter white and yellow form that is prevalent during the rest of the year. They are hard to spot because of their minute size and their habit of sheltering inside flower and leaf bud scales. Thus, a history of thrips-damaged fruit may be a better indicator of the presence of thrips than actually seeing them.
The tan or silvery, scabby scarring caused by thrips does not significantly harm the internal quality of the nectarine fruit, but the scarring is unsightly and has a coarse, leathery texture that is unpleasant to bite into. Fruit damage occurs when immature thrips nymphs feed on the surface of tiny fruit, just as it begins to develop. Feeding creates scars on the fruit surface and these scars enlarge as the fruit grows. These insects often begin feeding even before the flower petals have dropped from the newly forming fruit. Once fruits begin to enlarge and their skin becomes tougher, thrips start to feed on new tender leaves as leaf buds begin to open. Unfortunately, this means that by the time their damage is apparent, thrips may no longer be present on the fruit.
Western flower thrips are not easy to control. They overwinter as adults in weeds and grasses beneath fruit trees or in nearby fields. If these overwintering sites are disturbed (by mowing or cultivating, for example), the thrips have a tendency to migrate onto nearby fruit trees. The first line of defense in controlling thrips is to keep the area around fruit trees clean and weed free in the first place. If possible, nearby fields should be disked or mowed in the fall to further deny thrips a habitat for overwintering.
Another way to control thrips is to encourage their natural enemies. Green lacewings, predatory thrips, minute pirate bugs and tiny predatory wasps are among the beneficial insects that prey on western flower thrips. To encourage these beneficials, keep dust to a minimum and consider rinsing dust off plants. Also, avoid persistent pesticides because these chemicals harm beneficials as well as the targeted pests. In addition, it should be noted that the greater the diversity of plant species in the garden, the greater are the odds of providing a suitable habitat for beneficials. A final thing to note about biological control is that releasing natural enemies is unlikely to provide significant thrips control. In most situations, beneficials simply disperse soon after they are released.
If the cultural and biological controls described above do not provide adequate control, they can be used in conjunction with the most selective, least toxic insecticides available. Contact insecticides that do not leave persistent residues include insecticidal soaps, horticultural oils and neem oil. These oil sprays must thoroughly cover the affected trees and be used at the right rates to avoid phytotoxicity (toxic effects on plant growth). These products can also be harmful to natural enemies and pollinators, so the timing of their application is important. For example, spraying just after flower petals have dropped will limit how much exposure bees will have to these materials.
A somewhat more effective spray is spinosad, which is sold as Captain Jacks' Deadbug Brew, Green Light Lawn and Garden Spray with Spinosad 2, or Monterey Garden Insect Spray. Spinosad is toxic to certain natural enemies and to bees, so should not be sprayed when trees are flowering. As with any chemical control, be sure to read and carefully follow label directions. Avoid using organophosphates such as malathion, as well as carbaryl, or pyrethroids as these chemicals are highly toxic to beneficial insects and are not particularly effective against thrips.
For further information:
- UC IPM: Nectarine: Western Flower Thrips
- UC IPM: Pest Notes: Thrips
- OnTario Tender Fruit IPM: Western Flower Thrips
Photo credit: OnTario Tender Fruit IPM
By Brent McGhie, Butte County Master Gardener, December 9, 2016.
While farmers have historically planted hedgerows around fields to delineate boundaries, provide windbreaks and keep livestock from wandering, University of California research shows that hedgerows also provide many unintended benefits. Hedgerows have significantly fewer crop pests and more beneficial insects, such as pollinators and predatory wasps, than conventional field edges and these benefits extend into adjacent croplands. Hedgerows also provide habitat for insect-eating birds and other wildlife. Native bees benefit from the undisturbed habitat, as well as the nectar and pollen that hedgerows can provide. Additionally, hedgerows are useful in controlling dust, reducing sound pollution, and preventing erosion.
Urban and suburban landowners can reap these benefits by planting smaller trees and large shrubs to establish mini-hedgerows instead of fences or hedges. A scaled-down hedgerow will still attract pollinators, beneficial insects and birds. Hedgerows can also create corridors between wild spaces, allowing wildlife to more safely move through neighborhoods. As landscape designer Rebecca Lindenmeyr says, “Hedgerows can provide a slice of wild on the outskirts of a landscape design.”
If you decide to create a hedgerow, try to choose plants with a variety of heights. Different types of wildlife are adapted to living at different levels above the ground. Also, generally speaking, wider is better when it comes to hedgerows. The wider the planting area, the more room there is for a greater diversity of plants. The greater the diversity of plants in a hedgerow, the more likely it is that wildlife will find a suitable habitat there. Look for plants that provide food for wildlife. Selecting a variety plants that produce flowers, fruit, nuts, seeds, or nectar at different times of the year increases your chances of providing food for the greatest diversity of wildlife species.
Native plants are a logical choice for use in hedgerows. They are familiar sources of food and shelter for local wildlife species, and are well adapted to the local climate and soils. Large native shrubs that are suitable for residential hedgerows in our area include California redbud, toyon, many species of Ceanothus and manzanita, coffeeberry, desert willow and coyote brush. California bush anemone, Cleveland and white sage and buckwheat are more moderately-sized natives that can also be useful in hedgerows. Smaller native perennials include deer grass, California fuchsia, milkweed and penstemon. An added bonus is that, once established, all of these natives are at least moderately “deer resistant.” It is important to recognize, however, that if they are hungry enough deer will eat virtually anything.
Three larger nonnative plants that deserve consideration for incorporation into hedgerows are rosemary, Chinese fringe flower and chaste tree. All are adapted to our climate, deer resistant, and relatively easy to manage. If you'd like to see what these plants look like in a garden setting, the chaste tree and most of the native plants mentioned above can be seen in the Demonstration Garden being developed by Butte County Master Gardeners at the Patrick Ranch Museum. Whatever plants you decide to use, enjoy the natural beauty and other benefits of your hedgerow!
For further information on residential hedgerows, consult the following sources for this article:
Butte Co. Master Gardeners. "Make Room for Hedgerows!" Butte County Gardening Guide and Three-Year Gardening Journal (2015): 104 (with thanks to Eve Werner).
By Alicia Springer, Butte County Master Gardener, October 21, 2016.
Let's not oversell that last point.
Low maintenance does not mean no maintenance. A drought-tolerant garden renewal will require some watering, weeding, deadheading, and pruning—especially in the first year, as perennial beds, groundcovers, shrubs, and trees establish root systems, growth habits, and branch structures. If your garden maintenance routine has primarily involved writing checks to a lawn-care service, this may seem like more maintenance, not less. But an established, diversified water-wise planting can thrive without fertilizers, pesticides, herbicides, manicures, or the roar of weekly mowing and blowing. “Low-ish” maintenance means paying attention and responding—with clippers, pruners, weeders, and rake—to seasonal cycles of growth, flowering, and dormancy. It can require a modest investment in time and effort, but you will be rewarded with a sense of satisfaction that goes beyond simply cutting the water bill.
Plan before you plant. Decide on a manageable project area—start small. Determine preparation needs such as turf removal and weed control, and research low-maintenance plant selections that fit your space and vision. Be aware that some California natives go dormant and look pretty haggard by the end of summer, so you may want to mix them with in with species that bloom in the fall. A great place to start your research is the Butte County Master Gardeners website, with a detailed regional plant list and links to a wealth of online info: http://ucanr.edu/sites/bcmg/resources/garden/
Choose plants that support wildlife. If one of your goals is to provide habitat for pollinators, birds, and other fauna, research the best selections and how to care for them. Start at the National Wildlife Federation's Garden for Wildlife website: http://www.nwf.org/Home/Garden-For-Wildlife.aspx
Group plants with similar needs together. Don't create extra maintenance work for yourself by sticking an odd-plant-out amidst others that thrive together.
Set up drip irrigation. Moving a dripping hose around the landscape gets old, fast. To get new plantings with similar low-water needs established in the first summer, and then maintain them once established, automate watering with a zoned drip watering system on a timer, and plan the zones so they cover plantings that require the same frequency, amount, and type of irrigation.
Don't be a greedy gardener. Start small and keep it manageable.
Enjoy. Invest some time in “low-ish” maintenance, and reap the rewards of getting a little dirt under your fingernails—not only water conservation and wildlife habitat, but a hands-on relationship with your own garden environment.
By Barbara Ott, Butte County Master Gardener, September 23, 2016.
The abundance from summer vegetable gardens is extended through the winter and beyond by methods of canning, freezing and drying. But you can also give your summer vegetables a longer life span by saving their seeds.
Flowering vegetable plants can be cross-pollinated by wind or insects. This can cause even heirloom plants to produce offspring that are not true to the parent plant. Cross pollination can be minimized by planting just one variety of a vegetable, or by separating the different varieties with sufficient space between them. For example, do not plant hot peppers near sweet peppers. It is likely the sweet peppers will be hot if grown from their seeds the following season. The seeds from these peppers will not be true due to random pollination.
When friends and neighbors start saying “No thank-you” to zucchini, summer squash, and cucumbers, plan to let these vegetables set mature seeds, if they are not hybrids. Once this decision is made, production will decline. When saving seed, harvest from the best vegetables. Choose disease-free plants with desired qualities, look for the most flavorful vegetables, consider size, time from planting to harvest, and other 'best quality' characteristics.
The seeds in tomatoes, peppers, melons, summer squash, and cucumbers are ripe when the vegetables reach full color. Peppers will shrivel, tomatoes will be very soft, melons, summer squash, and cucumbers will be large. Pepper seeds can be taken out and dried. Tomato, melon, squash, and cucumber seeds are prepared with a wet method. Scoop the seed masses out of mature fruit. Put the seed mass and a small amount of warm water in a bucket or jar. Ferment for two to four days. Stir daily. The fermentation process kills viruses and separates the good seed from the bad seed. After two to four days, the good seeds will sink to the bottom of the container, while the pulp and bad seeds will float. Pour off the pulp, water, bad seed and mold. Spread the good seed on a screen or paper towel to dry.
Seeds must be stored dry. Make sure all containers or packages are labeled with the seed type or variety, and date of collection. Store in a cool dry location like a refrigerator. Seeds that are not dry enough before storage will mold. Seed viability will decrease over time. Most seed should be used within three years. As summer ends, enjoy the fruits of your labor, including saving some of your vegetable seeds for the future.
By Cindy Weiner, Butte County Master Gardener, September 9, 2016.
The bioswale on the campus of California State University, Chico collects rain water from the roof and grounds of the Student Services Center (SSC) as well as runoff from the south side of Meriam Library, the west side of Bell Memorial Union and the large plaza connecting the three buildings. When the SSC building was completed in 2008, the bioswale was one of the landscape elements required in order for it to receive silver certification from LEED (Leadership in Energy and Environmental Design).
Rainwater collected from the SSC is first drained into an underground cistern, where dirt and other particulates sink to the bottom. When the cistern is full, the water is pumped through a pipe into the bioswale. Runoff water from the plaza drains directly to the bioswale. As the runoff moves downslope through the bioswale, it slows down, allowing some water to infiltrate into the ground and the rest to slowly make its way into the campus storm drain system. Slowing down the runoff helps to keep the storm drains from flooding. The vegetation filters out some of the impurities in the water. Infiltration reduces the amount of water flowing into storm drains and helps recharge ground water. In some localities the native soil must be modified in order to increase the soil's capacity to accept so much water without flooding. The native soil on the Chico campus, however, has excellent drainage and did not require any further engineering.
The bioswale was remodeled in 2015 to make it more attractive and to provide a pleasant place for sitting and strolling without compromising its function. This remodel is the first major project on campus to be completely designed and installed by the Facilities Management Ground and Landscape Services Department. A dry creek bed of boulders and rocks was installed to reduce irrigation needs in the summer, and a walking path meanders the length of the bioswale. New vegetation includes two species of sedges that will spread by underground rhizomes to fill the space and a variety of native and non-native perennials and small shrubs to provide pops of color. The sedges are especially valuable in their ability to filter the water and are planted in the lower parts of the swale. The more colorful plants include yarrow, sticky monkeyflower, Matilija poppy, and Texas sage. Existing sycamore and redwood trees cast filtered shade that makes the area pleasant even in the summer heat. A bench formed from large blocks of Tuscan mudflow unearthed during a local residential construction project is an attractive place to sit and look at the plaza and its activities. Educational signage explaining the bioswale, plantings and Tuscan mudflow should be installed soon.
Bioswales are designed to handle large amounts of runoff in commercial or institutional settings. But home gardeners can make a rain garden to provide a similar function in their yards. Rain water from downspouts or runoff from hardscaped areas can be directed to an area where the water is slowed, collected, filtered and infiltrated into the ground. This would typically be an area that is lower than surrounding areas and landscaped with a variety of plants that can withstand periodic flooding during the rainy period. Soil drainage can be improved by adding compost or other organic material.