JoAnne Skelly, Carson City / Storey County Extension Educator, University of Nevada Cooperative Extension, ,

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1 Date: October 7, 2014 Spring Bulbs Need Fall Planting I m looking forward to planting daffodils this weekend. They were so lovely last spring; I want more. Spring flowering bulbs need fall planting and October is the best planting time. Once planted, bulbs require little maintenance for long-term visual pleasure. Among the most popular types of bulbs are tulips, narcissus, daffodils, hyacinths and crocuses. For the best display next spring, start with large firm bulbs. Smaller, less expensive bulbs will have less food reserves and will produce fewer flowers on weaker stems. Avoid bulbs with blemishes, discoloration, moldy skin or rotten bits. Select a site for planting where the bulbs will receive a minimum of five to six hours of sun each day, although daffodils, fritillaries or wood hyacinths will tolerate some shade. Ideally, the soil in your selected location should be porous and well drained. Dig a hole for each bulb, or dig one large area, big enough to hold all the bulbs in one drift. Bulbs planted in irregular patterns and masses of just one color look more natural than those planted in soldierly rows. Bulbs can be planted in with ground covers and other flowers. The general rule for planting depth is to plant bulbs two to three times as deep as the bulb diameter. Plant them as far apart as the depth at which they are planted four to six inches for large bulbs, one to two inches for small ones. In poorer draining soils, plant bulbs a little higher to prevent them from rotting. Loosen the soil in the bottom of the hole. Mix in compost and bone meal, superphosphate or a commercial bulb food into the bottom of the hole. Balanced fertilizers high in phosphorus (the second number in the analysis) such as a or

2 can be used instead. Plant the bulbs with the flat or concave side down and the pointed side up. Press the bulbs gently into contact with the bottom of the hole and cover with the amended soil. Tamp the soil down firmly around the bulbs. This will eliminate air pockets that prevent good root development. Water thoroughly and apply a 3-inch layer of mulch for winter protection. Water once every week or two through the fall and at least once a month through the winter. After a long winter of often-gray days and little color in the yard, that first burst of spring color will be a welcome sight.

3 Date: October 14, 2014 Why Do Leaves Change Color? Autumn has come gently this year with hot weather continuing into October. The leaves are finally turning color. At University of Nevada Cooperative Extension, Master Gardeners are often asked why leaves change color. Is the cold responsible? This seems logical, but it is not the complete answer. Many leaves start to change long before the cold weather hits. The most important factors affecting the colors are the change in daylight and day length. Four leaf pigments are responsible for the colors in leaves. These are chlorophylls, carotenoids, anthocyanins and tannins. At this time of year, leaves slow their foodmaking process (photosynthesis) preparing for winter shutdown. Chlorophyll begins breaking down and disappears from leaves. Chlorophyll gives plants their green color through spring and summer. When the green color fades, other pigments show through, such as the carotenoids, which give leaves their yellow and orange colors. Previously, these colors were hidden by the green chlorophyll. Although temperature does influence the process, day length and the reduction of chlorophyll production are the controlling factors.

4 Other plant chemical changes also occur during autumn producing the red and purple colors we see in plants such as sumac, Virginia creeper, burning bush and others. The fall weather conditions that favor brilliant red color are warm sunny days with crisp nights without freezes. The cooler nights trap sugars that were produced in the leaves during the sunny day. This allows the anthocyanin pigments to produce red color tones. Anthocyanins are usually only produced in the fall. Tannins produce the brown tones in fall leaves. They accumulate in dead tissue. Brown leaves are simply waste materials leftover in leaves. Fall color is also affected by what happened to the plant during the growing season, particularly in regards to moisture. Rainy cloudy weather can reduce fall color because sugar production is reduced when there is less light intensity. Summer drought can play a role by delaying the onset of fall color by a few weeks. Since soil moisture varies from year to year, no two autumns are ever alike. Color intensity varies with location, from sunny exposures to shady ones. Color can even vary on individual trees or by tree types. Early frosts weaken the strong colors because leaves are injured by the cold. Call or skellyj@unce.unr.edu for a free copy of Preventing Winter Injury to Landscape Plants.

5 Date: October 21, 2014 A Bee-friendlier Society In 1945 there were 4.5 million bee hives in the US. Today, there are just about 2 million. We average a 30 percent loss of beehives in winter each year. Twenty years ago that was 15 percent.. So reports Dr.Marla Spivak, entomologist, University of Minnesota Bee Lab in a 2013 Ted Talks presentation. She says there are 20,000 species of bees in world. Most live in the ground or in hollow stems rather than in social colonies as honeybees do. Within a colony, bees have natural defenses that have kept them thriving for over 50 million years. However, seven years ago, bees started dying from multiple, interacting causes: disease-causing parasites, monocultures of plants, pesticide contamination, flowerless landscapes and a dysfunctional food system. In the US, bee numbers have been declining since World War II when we changed our farming practices. We stopped planting clover and alfalfa cover crops, which were an excellent food source for bees and started using synthetic fertilizers instead. We began applying more herbicides, killing weeds whose flowers were a food source for bees. Now farms are agricultural food deserts for bees, because they are usually dominated by single species (monoculture) of plants. For example, even though almond flowers are a good pollen source for bees, over 1.5 million hives must be transported across the country to pollinate tens of thousands of acres of almonds. Nothing else is growing, just almonds. The bees are trucked in on semis and trucked out after pollination, since at that point, there is no more food for them. After World War II, farmers also increased their use of fungicides and insecticides, in addition to herbicides. Researchers at Penn State University have been studying pesticide residues in the pollen bees are carrying home. They found that every batch of pollen in their study had about six pesticides in it, including not only the toxic active ingredients in the herbicides, fungicides, insecticides, but also the inert ingredients that can be more toxic than actual chemical. What can we as gardeners do? We can plant bee-friendly flowers, particularly native plants that bloom in each season. We can avoid pesticide contamination, at least in our own yards. We can ask that pollen sources be planted in parks, open spaces, along roadsides, etc. We can give bees access to good nutrition, which will allow them to take care of their own health. We can be a bee friendlier society. For more information go to:

6 Date: October 28, 2014 Herbicides and Weed Resistance The Environmental Protection Agency (EPA) sent out a press release announcing a decision to register a new herbicide that contains two active ingredients, 2,4-D and glyphosate. These two ingredients are the most widely used herbicides in the world for controlling weeds. Local gardeners use 2,4-D to kill dandelions in lawns and glyphosate to kill just about anything green. This new herbicide combo is designed primarily to kill weeds in corn and soybeans; crops that have been genetically engineered to tolerate both chemical compounds. EPA scientists used very conservative assessments to evaluate not only the human health risks, but also the ecological risks. The agency evaluated the risks to all age groups, from infants to the elderly, and took into account exposures through food, water, pesticide drift and as a result of use around homes. The decision meets the rigorous Food Quality Protection Act standard of "reasonable certainty of no harm" to human health. The assessments confirm that these uses meet the safety standards for pesticide registration and, as approved, will be protective of the public, agricultural workers and non-target species, including endangered species. While genetically engineering plants to tolerate chemicals that would normally kill them allows farmers to kill weeds more easily, weeds quickly build up resistance to new herbicides. In a few years, the herbicides no longer work to control weeds in the crop and new chemicals must be created or combined and additional genetic engineering must occur. Resistant weeds become quite costly to a farmer, who no longer can use that method of control. Those costs are usually passed on to the consumer. To ensure that weeds will not become resistant to the 2,4-D/glyphosate combo, EPA is imposing a new, robust set of requirements on the company registering the product. These requirements include extensive surveying and reporting to EPA, grower education and remediation plans. The registration will expire in six years, allowing EPA to revisit the issue of resistance. In the future, the agency intends to apply this approach to weed resistance management for all existing and new herbicides used on herbicide-tolerant crops. Although this combination herbicide may not be registered for use in Nevada in the near future, home gardeners, farmers and others use many other herbicides. Overuse of any herbicides or repeated use of the same herbicide can create resistance in the common weeds we deal with in Nevada. Use herbicides as a last resort. If you do apply herbicides, use products with different active ingredients each year to avoid creating resistant weeds.