Genetics and GenomicsCameron Peace, Dorrie Main, Amit Dhingra and others are working to apply basic genetic science to accelerate the development of Washington-specific tree fruit varieties. Building on the Genome Database for Rosaceae (GDR), tree fruit Genome Database Resources (tfGDR) will provide fundamental bioinformatics and database capabilities for Rosaceae and Citrus. It will be designed specifically to meet the needs of basic, translational and applied researchers, and industry stakeholders, facilitate the discovery of genes underlying important agricultural traits, develop markers for genomics-assisted-breeding, and enhance critical decision-making by apple, cherry, peach, strawberry and citrus breeders and growers. (more…)
Factors Affecting Bee Pollination of Tree FruitsNearly 1,000 species of bees occur in the Pacific Northwest, but only a small number of species are useful in the pollination of orchard crops. Pesticide use and loss of appropriate nesting habitat have reduced the numbers of wild bee pollinators, leaving most of the pollination for commercial orchards dependent on honeybees. The success of honeybee pollination in tree fruits is affected by a number of factors, which in part can be manipulated by orchardists and beekeepers.
Foraging Behavior of Honey BeesAt any given time approximately one-third of the honeybees in a colony are searching, or foraging, for nectar or pollen. Foraging bees rarely collect both nectar and pollen during the same flight. About 50% of the honeybees foraging in Red Delicious apples are pollen collectors, but that number may increase in other varieties. Roughly 80% of the honeybee foragers in cherry orchards are collecting pollen. Because pollen collectors pollinate fruit trees more efficiently than nectar collectors, orchardists prefer colonies with a higher percentage of pollen collectors. Larger colonies, with large amounts of brood (immatures) tend to send out a greater proportion of pollen collectors than small colonies. (more…)
IntroductionWashington State University has been involved with organic agriculture for decades. Organic agricultural research started at WSU in the 1970’s and an organic major was introduced for undergraduate students in 2006. In 2007, WSU purchased a new research farm with over 100 acres of certified organic production already in place. Orchardists worldwide are increasing their use of organic and sustainable production systems due to consumer preferences and land and environmental stewardship priorities. Organic tree fruit production has provided a valuable commodity for growers in the state of Washington for over a decade. Numerous resources on organic production can be found on this page including: current research; certification; orchard establishment; insect pest management; disease management; tree fruit nutrition; weed control; tree training systems; packing and storage; vertebrate pest management; and food safety. (more…)
Pollination – Sweet CherryMost sweet cherry varieties are self-unfruitful (self-incompatible, SI) and require cross pollination with another variety as the pollen source. Some varieties, e.g. Bing, Lambert, Royal Ann/Napoleon, are also cross-unfruitful and cannot be depended upon to provide pollen for each other. Index, Lapins, Skeena, Sweetheart, White Gold, Sonata, Stella, Symphony, Sunburst, and Black Gold are self-fruitful (SF) and can serve as “universal” pollen sources for many self-unfruitful varieties with the same bloom time. However, Stella has been found to not work as a pollinator for Bing in some areas. Their use as “universal” pollinators should also take bloom timing into consideration as follows. Early-bloom: SI – Somerset; SF – Lapins and Skeena. Early- to early-mid-bloom: SI – Kristin, Chelan, and Black Republican; SF – Sweetheart and WhiteGold. Mid- to late-mid-bloom: SI – Royalton, Summit, Ranier, Royal Ann / Napoleon, Bing, Burlat, Van, Regina, Lambert, Sam, and Windsor; SF – Sonata, Stella, Symphony, and Sunburst. Late-bloom: SI – Gold and Hudson; SF – BlackGold. Move bees into orchards on the first day of bloom. The pollination table below is a partial guide to help select pollen source parents. (more…)
Rootstocks for CherryAll commercial cherry trees are made up of two parts: the upper fruiting portion (grafted or budded scion wood); and the lower portion ( the rootstock). Until fairly recently, the majority of breeding efforts were directed towards fruit improvement. Over the past century, breeding programs have concentrated mainly on achieving improved characteristics such as yield, taste, fruit size, fruit firmness, fruit color, precocity, and resistance to fruit cracking and disease. In contrast, rootstock development has only recently received breeders attention. It is believed that 'Mazzard' seedlings are the oldest known sweet cherry rootstock dating back to the early Greeks and Romans. And this is still the most widely used rootstock for sweet cherry throughout the Pacific Northwest. Many of the newer rootstocks are described using Mazzard as a standard for comparison. Recently, several new rootstocks have gained prominence for their improved attributes. Many of these are semi-dwarfing. Some of these may impart some disease resistance, induce precocity (bearing younger, and lend themselves to use in high-density plantings. There is an excellent PNW Extension publication by L. Long and C. Kaiser reviewing the performance of the major sweet cherry rootstocks grown around the region. (download pdf PNW619) Listed below are many of the sweet cherry rootstocks available for use in the Pacific Northwest. (more…)
Six Steps to Calibrate and Optimize Airblast SprayersBy Gwen Hoheisel, WSU Regional Extension Specialist The idea behind any pesticide application is to get every drop to the crop. Spray or drift that goes into the air clearly missed the target leading not only to negative environmental and health effects, but also a waste of money. Pesticide applications are the most frequent operation carried out in the orchard or vineyard, and chemical control is the second highest cost of production (i.e., pre-harvest operations) in orchard systems with material costs for a single spray ranging from $40 to > $100/acre depending on the crop and chemical (Freeman et al., 2008). So any waste, or improvement, can have a significant economic impact. . Proper maintenance and operation of a sprayer is the first step in optimizing spray quality. This article will discuss 6 steps to calibrate and optimize sprayer output. However, there is an assumption that the mechanical parts of a sprayer—like the hoses, pressure gauges, pumps, and agitators—are working properly. Optimizing spray applications takes time initially, but will pay off with better coverage, improved pest control, and less culls. (more…)
Varieties – CherryTwo main types of cherries are produced in the United States: sweet cherries and tart or ‘sour’ cherries. Washington, California and Oregon are the primary sweet cherry producing states, accounting for more than 97 percent of the quantity produced nationwide (NASS 2013). The primary tart cherry producing state is Michigan, which typically accounts for nearly 90 percent of tart cherry production. U.S. sweet cherry production in 2012 totaled 424,000 tons valued at more than $843.3 million. Washington led the nation in sweet cherry production, with 264,000 tons, followed by California (92,300 tons) and Oregon (56,000 tons) (NASS 2013). The United States is the third-largest producer of cherries in the world. The European Union-27 is the leading cherry producer, followed by Turkey (FAS 2012). "Bing" has been one of the most important sweet cherry varieties grown in the Pacific Northwest as recently as the 1990's. "Bing" is so commonly known that it is used as a basis of comparison when discussing sweet cherry selections. For example, ripening time for a variety may be referred to as being a set number of days before or after "Bing". In recent years, there has been more interest in improved varieties leading to extensive plantings of newer selections. Some traits that breeders are selecting for include early maturing, self-fertility, rain cracking resistance and stem characteristics. The majority of the newer varieties grown in the Pacific Northwest were produced or evaluated by the following breeding programs: WSU-IAREC - Prosser; the Pacific Agri-Food Research Centre (PARC) Summerland, B.C., Canada; and the OSU cultivar evaluation program. Additional sweet cherry variety and/or rootstock trials are carried out at WSU's Western Washington Maritime Research and Extension Center in Mt. Vernon, WA and at WSU Tree Fruit Research and Extension Center in Wenatchee, WA and at their associated Sunrise research orchard. A few other sweet cherry varieties grown in lesser amounts are a product of the New York State Agricultural Research Station at Geneva, NY and from Michigan State University's breeding program. The most commonly grown sweet cherry varieties in the Pacific Northwest are shown below in the thumbnail gallery and are arranged by color group. Click on the image to open the full view for information about each variety. (more…)
Weed ManagementOrchard drive rows (alleyways) between tree rows are usually covered with grass, or some other cover crop that is easily mowed. Ground cover is important in tree fruit orchards to inhibit soil loss and erosion, provide traction for tractors and other equipment, and to help with water infiltration and drainage in the soil. Weeds, on the other hand, are defined as “plants out of place.” Weed seeds blow in on the wind, come through irrigation water, and are carried by birds and other animals. Perennial weed species regrow each year from below-ground parts. Tree fruit growers need to continually manage weeds in orchards, especially in the “weed-strip,” the three to eight feet wide band under the trees, in the tree row. Because the weed-strip is difficult to mow (e.g., low-hanging branches, tree trunks, trellis posts and irrigation systems), other weed management methods are generally used in that region. There are many benefits to controlling weeds in orchards year-round:
- Weeds compete directly with fruit trees for needed water and nutrients during the growing season. This is particularly so for young trees. Keeping the weed-strip mostly clear of weeds can save the grower between 50,000 and 100,000 gallons of water per acre per year.
- Weeds can interfere with irrigation of the trees by blocking the sprinkler pattern, causing uneven or inefficient irrigation, or by plugging sprinklers. Micro-sprinklers are even more susceptible than other styles of sprinklers because they are often low to the ground. This is not a problem with drip irrigation.
- Serious weed competition can cause young trees to have stunted growth, reduced fruit size and yield. This can result in significant economic losses.
- Certain insect pests of tree fruit that live in host-plant weeds can multiply there and migrate up into the trees causing direct damage to the fruit resulting in significant economic losses.
- Tree-damaging rodents (see links below) like to hide and overwinter in the habitat created by weed cover and while there, they feed on tree bark and roots and cause damage. Rodent pests (meadow voles, mice, etc.) will be deprived of habitat next to trees if weeds are controlled, especially in the fall.
- Significant weed cover under trees also makes worker and machine access difficult (e.g., dangerous for ladder work).