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We initiated a study in 1986 to determine the feasibility and cost of establishing low shrub cover on islands. Woods rose and snowberry were planted during May on 1 upland and 4 island sites in 1986 and 1987. The species were set alternately at a 2-foot spacing. Each plot was hoed 3 times during the growing season to reduce weed competition. We used power augers, KBC bars, OST bars, steel bars, and tile spades to plant shrubs.

Survival of snowberry was 50% after the 2 growing seasons and plant height averaged 8.9 inches. Woods rose survival averaged 74% after 2 growing seasons and plant height averaged 14.6 inches. Shrub survival was only 17% for snowberry and 70% for rose at Medicine Lake where weed control was ineffective. Only 30% of the snowberry and 47% of the rose survived at the Thacker Waterfowl Production Area where weed control was adequate but plants were placed into subsoil. At 2 sites where there was good topsoil and good weed control, shrub survival and growth was excellent. At these sites plant survival was 98% and the average height of Woods rose exceeded 19 inches after 1 growing season.

It would require 3,484 seedlings to plant 0.5 acre plot if shrubs were spaced 2.5 feet apart. Using our average cost of 0.29/plant the total expense for shrubs would be $1,001.65. An estimated 16.9 man-days would be required to plant the shrubs and 3 visits for weed control would involve another 15.6 man-days.

As a result of trials we make the following recommendations for establishing low shrubs on islands:

1. Plant in early May after the last threat of severe frost.
2. Plant into topsoil where the weeds have been eliminated.
3. Space plants 2.0 to 2.5 feet apart so a dense canopy forms when plants reach full growth.
4. Use a KBC bar for planting and pack soil tightly around the plant roots.
5. Maintain the shrub Plots as weed free as possible during the first 2 growing seasons. Eliminate weeds in the first year by hoeing and apply Dichlobenil in the fall of the first year to aid weed control the second year.