mate and harden in the fall before cold temperatures ensue, as indicated by loss of shoot tips to cold damage after the first and third winter. Enhancement of growth by use of grow tubes should be managed closely. The tubes should be removed sometime late in the first growing season, and not allowed to remain on through the winter as occurred in this study. Though rates of N used in this study would not normally be considered excessive, it is likely rates, timing and possibly source of N may play a role in winter hardiness.
Early management requirements for success with pawpaw appear to be minimal if good site preparation and care are provided the trees in early years. As for sustainability, no insecticides or fungicides were used to grow the trees in this study, and mulching kept weed competition to a minimum. Because no current herbicide is registered for the crop, mulch is an advantage, though as an observation, trees seemed slower in breaking dormancy with mulch use, and N applications should be adjusted to compensate for chip breakdown. This site harbored large populations of rodents (meadow voles) under the mulch, however no damage was noted in the planting, indicating a lack of preference for pawpaw wood tissue. However, rodent populations should be monitored when mulch is used. On this site deer pressure was also heavy, but only minor feeding activity was observed on trees in this study.
In summary, variety and seedling survival rates were high under these particular cultural conditions, though there was evidence of cold damage to shoots if inadequately hardened in the fall. Differences in growth were observed between grafted varieties on a genetically similar rootstock, and between grafted and seedling trees. Grafted varieties developed flower buds by the spring of the fourth season, however the percent of flowers developing from buds was a variety dependent, and no fruit was set from them. Seedling trees remained juvenile and did not develop flower buds.
survival rates were high under these particular cultural conditions, though there was evidence of cold damage to shoots if inadequately hardened in the fall. Differences in growth were observed between grafted varieties on a genetically similar rootstock, and between grafted and seedling trees. Grafted varieties developed flower buds by the spring of the fourth season, however the percent of flowers developing from buds was very dependent, and no fruit was set from them. Seedling trees remained juvenile and did not develop flower buds.
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