Issue link: https://read.dmtmag.com/i/314286
T he following observations regarding replant-tolerant Geneva rootstocks have been made as a result of trials in Washington: • The high yields from these rootstocks can cause the scion to slide off the rootstock, especially when the trellis fails. Trel- lis engineering should consider 100 bins per acre as the typical load for vertical trellis. Limbs should be attached to wire with five wraps of electrical tape to prevent trunks from sliding down the trellis or twist- ing in high winds. Post intervals down the row should be less than 40 feet. Wire tension is critical to trellis strength. A properly tensioned wire should not deflect more than three-fourths of an inch with substantial force applied. It is too common to encounter trellises where the top of the tree can be pushed a foot or more from center, allowing a swing of two feet. Collapse is likely with loose wires and a crop load of 70 or more bins per acre. Another major flaw of many trellises is that the anchor is placed too close to the end post. The anchor must be at least as far away from the end post as the height of the top wire. For example, if the top wire is ten feet from the ground, the anchor must be ten feet from the end post. • When replacing trees in established orchards, the replant- tolerant Geneva rootstocks have consistently demonstrated their superior characteristics. • The M.26-class Geneva rootstocks are far more productive than M.26, M.7, or M.106, especially as the trees become older with larger- caliper wood. "M.26 class" is the term applied to the rootstocks that will 34 JUNE 2014 GOOD FRUIT GROWER www.goodfruit.com New Varieties Third-leaf Fuji on Geneva 214 rootstock in unfumigated ground at Brewster, Washington. Helicopter Aerial Spraying SERVICES: • Farm Ground / Crop Land "Crop-dusting" • Noxious Weeds in Pastures and Rangeland • Water Ways, Marshes, Lakes, and Ponds • Aerial Seeding and Fertilizing • Fruit Orchards • Timber and Forestry • Cherry Drying Providing excellence in precision aerial applications throughout the Pacific Northwest. CALL FOR A QUOTE! 208-743-5411 Office 208-790-1122 Doug Lohman MORE INFO AT www.LohmanHelicopter.com LOW. SLOW. ACCURATE. Minimize drift, maximize yields and profits. GENEVA in Washington Trials in Washington's arid climate are revealing more about how the new Geneva rootstocks perform. by Tom Auvil, Washington Tree Fruit Research Commission