Bahiagrass (Paspalum notatum Flugge cv. Paraguayan-22) growing under newly planted peach [Prunus persica (L.) Batsch.] trees severely stunted the trees. Neither supplemental fertilizer nor irrigating with two 3.8-liters·hour-1 emitters per tree eliminated tree stunting emitters were controlled by an automatic tensiometer set to maintain 3 kpa at a depth of 0.5 m under a tree in bahiagrass. Preplant fumigation with ethylene dibromide at 100 liters·ha-1 increased tree growth, but not tree survival. Fenamiphos, a nematicide, applied under the trees each spring and fall at a rate of 11 kg-ha -1 had no positive effect on tree survival, tree growth, or nematode populations. Bahiagrass tended to suppress populations of Meloidogyne spp. under the trees., Meloidogyne spp. were the only nematodes present that had mean populations > 65 per 150 cm3 of soil. Leaf concentrations of several elements differed between trees growing in bahiagrass sod and in. bare ground treated with herbicides. Leaf Ca was low for all treatments in spite of a soil pH near 6.5 and adequate soil Ca. The severe stunting of trees grown in bahiagrass, irrespective of the other treatments, demonstrated that bahiagrass should not be grown under newly planted trees. The low populations of parasitic nematodes in bahiagrass showed that bahiagrass has potential as a preplant biological control of nematodes harmful to peach trees. Chemical name used: ethyl 3-methy1-4-(methylthio) phenyl (1-methylethyl) phosphoramidate (fenamiphos).
Dean R. Evert, Paul F. Bertrand, and `Benjamin G. Mullinix Jr.
Umedi L. Yadava
A planting of 90 Redhaven peach (Prunus persica (L) Batsch) trees either budded to Lovell and Nemaguard rootstocks or on their own roots, was established in spring 1984 using in-ground 55-gallon microplots. Planting soils (top soil, not B and C layers) prepared in five ratios by mixing soils from peach tree short life (PTSL) and non-PTSL (NPSL) sites (100% PTSL, 75% PTSL + 25% NPSL, 50% of each, 25% PTSL + 75% NPSL, and 100% NPSL) as main plots, were replicated 3 times. Two trees per rootstock were randomized within main plots. The planting was maintained using conventional cultural practices. Observations for tree survival were recorded in December each year. During this investigation, both soil mix and root types significantly affected tree survival, which was consistently the highest in 100% NPSL and the lowest in 100% PTSL soil. Effects of other soil combinations were intermediate; however, greater tree mortality was associated with increased ratio of PTSL soil. Trees on Lovell roots invariably survived the best followed by those on Nemaguard roots and the lowest when on their own roots. As early as in fourth leaf, >55% of the own-rooted trees died compared to < 10% on either rootstock.
Richard C. Funt, Mark C. Schmittgen, and Glen O. Schwab
The performance of peach trees [Prunus persica (L.) Batsch cv. Redhaven/Siberian C.] on raised beds as compared to the conventional flat (unraised) orchard floor surface was evaluated from 1982 to 1991. The raised bed was similar to the flat bed in cation exchange capacity (CEC), Ca, P, K, Mg, B, and Zn soil levels in the 0-15 cm depth. Microirrigation, using two 3.7 L.h-1 emitters per tree vs. no irrigation, was applied to trees planted in a north-south orientation on a silt loam, noncalcareous soil. Raised beds increased trunk cross-sectional area (TCA) and yield-efficiency over 5 years. Irrigation increased fruit mass mostly in years of highest evaporation. Significant year to year variations occurred in yield, fruit mass, TCA and yield efficiency. There were significant bed × year interactions for yield and TCA. Irrigation increased leaf boron content regardless of bed type. Leaf potassium was higher in flat beds. Nonirrigated trees had the lowest tree survival on the flat bed, but the opposite was true on the raised bed.
Richard E.C. Layne, Chin S. Tan, and David M. Hunter
Three cultivars (`Garnet Beauty', `Harbrite', `Canadian Harmony'), two ground covers (temporary cover vs. permanent sod), and no irrigation vs. season-long trickle irrigation were studied in a high-density (633 trees/ha) peach [Prunus persica (L.) Batsch] orchard established on Fox sand in 1980. From 1985 to 1989, soil water content in the top 130 cm was similar in nonirrigated and trickle-irrigated plots except during the growing season (May to September). Total soil water was lowest in nonirrigated plots that had permanent sod strips in the row middles and fell below the-permanent wilting point for ≥11 months in summer but not at depths below 130 cm. Trunk cross-sectional area (TCA) was greater for `Canadian Harmony' and `Harbrite' than `Garnet Beauty', ground-cover treatments had no effect, and irrigated trees were generally larger than those not irrigated. Photosynthetic rate and stomatal conductance differed by cultivar, were unaffected by ground cover, and were enhanced by irrigation. Defoliation differed by cultivar, ground cover had little effect, and irrigation usually delayed defoliation. Flower bud and shoot xylem hardiness differed by cultivar but not by ground cover and were generally enhanced by irrigation. Tree survival was significantly affected by cultivar, being best with `Harbrite' and `Canadian Harmony' and poorest with `Garnet Beauty'. Permanent sod enhanced tree survival while trickle irrigation reduced it. Cumulative marketable yields were affected more by cultivar than by ground cover or irrigation. `Canadian Harmony' had the highest yield, followed by `Harbrite', then `Garnet Beauty'. Yields in sod were slightly higher than in temporary cover and yields with trickle irrigation were slightly higher than without irrigation. The best soil-management system when TCA, marketable yield, and tree survival were considered was a combination of permanent creeping red fescue sod strips in the row middles and trickle irrigation in the tree row. This system is being recommended to commercial growers in southwestern Ontario.
Christina Wells, Karen Townsend, Judy Caldwell, Donald Ham, E. Thomas Smiley, and Michael Sherwood
Landscape trees are frequently planted with their root collars below grade, and it has been suggested that such deep planting predisposes trees to transplant failure and girdling root formation. The objective of the present research was to examine the effect of planting depth on the health, survival, and root development of two popular landscape trees, red maple (Acer rubrum) and `Yoshino' cherry (Prunus ×yedoensis). Trees were transplanted with their root flares at grade, 15 cm below grade or 31 cm below grade. Deep planting had a strong negative effect on the short-term survival of `Yoshino' cherries. Two years posttransplant, 50% of the 15-cm- and 31-cm-deep planted cherries had died, whereas all the control cherries had survived (P< 0.001; 2). Short-term survival of maples was not affected by planting depth. Deep-planted trees of both species exhibited little fine root regrowth into the upper soil layers during the first year after transplant. Four years posttransplant, control maples had 14% ± 19% of their trunk circumference encircled by girdling or potentially-girdling roots; this number rose to 48% ± 29% and 71% ± 21% for 15-cm- and 31-cm-deep planted maples, respectively (P< 0.01; ANOVA main effect). There were no treatment-related differences in girdling root development in the cherries.
Frederic B. Ouedraogo, B. Wade Brorsen, Jon T. Biermacher, and Charles T. Rohla
effect on tree survival, but did increase growth rate so that there was no difference in the height of pruned and unpruned tress after 3 years; however, Smith and Johnson (1981) found that survival was increased by pruning the tops at planting by 25% or
Andrew K. Koeser, J. Ryan Stewart, Germán A. Bollero, Donald G. Bullock, and Daniel K. Struve
, trees are exposed to mechanical shock and vibration that can further disrupt the root system and cause considerable damage to trunks and crowns. Water is typically not available during transport; tissue desiccation can greatly affect tree survival if
Lawrence R. Parsons, T. Adair Wheaton, and George Yelenosky
Handwarmers placed inside conventional insulating tree wraps increased trunk temperatures and improved tree survival under freeze conditions. Handwarmers generate heat by oxidation of Fe powder. In freeze-chamber tests with air temperature as low as –7.1C for 4 hours, wraps plus handwarmers kept trunk temperatures above freezing. Handwarmers increased minimum temperatures by 7C during a one-night freeze. Benefit of the handwarmer decreased the second night of a simulated two-night freeze but still increased minimum temperature by 1.3C. Tree survival was significantly improved by handwarmers in the freeze-chamber tests. In a field test during a mild freeze, handwarmers increased the minimum temperature by 3.5C the first night but provided no benefit the second night.
J.D. Norton, G.E. Boyhan, and J.A. Pitts
The dwarfing characteristics of St. Julien and Pixy rootstocks as measured by shoot growth and trunk cross-sectional area (TCSA) was evident. Tree survival was significantly reduced after 3 years on Nemaguard and Pixy rootstocks. None of the elements measured by foliar nutrient analysis were below the minimum for plums; however, significant multiple regression equations for total shoot growth, TCSA, and survivability were evident with R 2 of ≈0.30 in all three cases.
Dean R. Evert and Paul F. Bertrand
More peach [Prunus persica (L.) Batsch.] trees survived when planted in killed bahiagrass (Paspalum notatum Flugge `Paraguayan-22') sod growing between previous orchard tree rows (98%) than when planted in previous tree sites (81%) or in previous tree rows, but halfway between previous tree sites (79%). The previous orchard was removed Nov. 1986, and new trees were planted Feb. 1987. Surviving trees in the killed sod grew better than trees at the other two sites. Tilling the sites before planting did not affect nematode populations or tree survival and growth. Soaking the tree roots in a fenamiphos solution (1 g·liter-1) for 20 minutes before planting resulted in 79% tree survival vs. 93% survival for the nonsoaked trees. Fenamiphos sprayed under the trees at a rate of 11.2 kg·ha-1 during the spring and fall of the planting year did not change nematode populations, tree survival, or tree growth. The fenamiphos sprays reduced the increase in trunk cross-sectional area by 3 cm2 for trees in the sod. Other than leaf Zn concentration, which was low, concentrations of the elements were within the sufficiency range for Georgia for all treatments. Trees planted in the killed sod had an increased leaf K concentration and decreased leaf Mg concentration when compared with trees planted in the rows. Chemical name used: ethyl 3-methyl-4-(methylthio)phenyl (1-methylethyl)phosphoramidate (fenamiphos).