The vegetative growth and fruit yield of three types of micropropagated `Redwing' red raspberry (Rubus idaeus L. var. idaeus) nursery stock were compared. The three types of nursery material included: 1) stage IV (S-IV) actively growing plants; 2) dormant-stage IV (DS-IV) plants; and 3) nursery-matured (NM) S-IV plants, grown for 8 to 12 weeks in the field before harvest for cold storage. On 1 Apr. 1991, primocane-fruiting `Redwing' plants of each type were planted 0.6 m apart in ridged, drip-irrigated, and straw-mulched rows spaced 3 m apart in six, three-plant replications. In the establishment year, a small, but commercially viable, crop was harvested from 16 Aug. 1991 to 28 Oct. 1991. The S-IV and NM plants produced greater yields than DS-IV plants in the establishment year. However, by the end of the second year, the S-IV plants had the greatest fruit yield, followed by NM, with the DS-IV plants continuing to have the lowest yield. Fruit size of the S-IV plants was largest in both years. While there were differences in dry weight during the planting year, by the experiment's conclusion, the dry weights were similar among all nursery types. When planting `Redwing', the less-expensive, easier-to-handle, and higher-yielding S-IV plants would be recommended over the other nursery types.
Two experiments were conducted to determine if 5.1-cm-caliper (2 inches) `Summit' green ash (Fraxinus pensylvanica), and 7.6-cm-caliper (3 inches) northern red oak (Quercus rubra) could be successfully summer transplanted after being heeled in pea gravel or wood chips prior to planting in the landscape. Spring harvested trees of each species were either balled and burlapped (B&B) or barerooted before heeling in pea gravel or wood chips. Compared to B&B `Summit' green ash, bareroot stock had similar survival and shoot extension for three growing seasons after summer transplanting. Bareroot and B&B northern red oak trees had similar survival and central leader elongation for 3 years after summer transplanting. In the third year after transplanting, northern red oak bareroot trees heeled in pea had smaller trunk caliper than B&B trees heeled in wood chips. These two taxa can be summer transplanted B&B or bareroot if dormant stock is spring-dug and maintained in a heeling-in bed before transplanting. This method of reducing transplant shock by providing benign conditions for root regeneration can also be used to extended the planting season for field-grown nursery stock; the method is called the Missouri gravel bed system.
Micropropagated `Redwing' raspberry plants were grown with various mulch treatments to determine their influence on vegetative growth and fruit yield. Treatments included shredded hardwood bark mulch; degradable black plastic; sawdust; wheat straw; ground, shredded, or ground + shredded newspaper; and an unmulched control. During the year of establishment, high soil and air temperatures near the surface of the black plastic most likely reduced plant survival. The following year, vegetative growth and fruit yield of plants that were previously mulched with black plastic were also reduced. Plants mulched with bark, sawdust, straw, and all newspaper treatments had greater yields than those established with black plastic or in the unmulched control plots. Although yields were similar among plants in all newspaper mulch treatments, ground newspaper was lost under windy conditions and tended to mat down after rainfall, resulting in soggy soil conditions.
The growth and fruiting of 3 types of micropropagated red raspberry plants were compared. The 3 types of nursery material included: 1) Stage 4 (S-4) - 10-15 cm tall, actively growing plants; 2) dormant Stage 4 (DS-4); and 3) nursery matured (NM) - S-4 plants that are grown for 8-12 weeks in the field. On 1 Apr. 1991, `Redwing' plants of each type were planted 0.6 m apart in ridged, drip-irrigated, and straw-mulched rows spaced 3 m apart. Fruit harvest began on 16 Aug. and continued until 28 Oct. On 12 Nov., the above ground portion of each plant was harvested for measurements of plant growth. The S-4 and NM plants had the highest fruit yields (number and weight), and the S-4 plants had the largest fruit size. NM plants had the first ripe fruit followed 4 days later by S-4 plants and 10 days later by DS-4 plants. The NM and S-4 plants had the greatest cane lengths and diameters. The S-4 and DS-4 plants had the largest above ground dry weights. The DS-4 plants produced the largest number of canes.