long, spaced 6 inches apart and running across the bed, to allow for hoe cultivation. The seeds may be sown about one-fourth inch apart with the expectation of obtaining germination and growth sufficient to get good seedlings every 2 inches apart. This would give an average of about 1,200 no. 1 seedlings on every 100 square feet of planted area, or allowing for beds 4½ feet in width, a gross area of 112½ square feet.
The seeds may be covered one-fourth inch in depth, preferably with a sandy loam soil which will not crust or bake in the sun after rains. A fundamental requirement is good moisture and warmth during the germination period, which in warm spring weather may be 10 to 14 days. To maintain such conditions a light mulch of clean straw, pine straw, or leaf litter is often desirable.
Much depends upon the weather conditions, which are normally variable from year to year as well as day to day. One method is to wait until late spring or early summer (June), sow the seed in beds that are well-soaked by rain or watering, cover the seed lightly with sifted soil, then mulch with straw or leaf litter to maintain good heat and moisture conditions. As soon as the seed begin to germinate it is very necessary to remove most of the mulch. This method of late sowing is often used where watering equipment is available to force the growth during dry spells. Otherwise the spring sowing is often best to take advantage of the spring moisture. Heavy watering during the season is usually inadvisable because it results in too large seedlings. A desirable size of seedling is from 12 to 18 inches in height. However, excellent results have followed with small trees averaging some less than 12 inches in height. In any event, a prime factor for good planting stock is a medium top and well-developed taproot like a long radish in shape. All seedlings with slender taproots may be regarded as culls, particularly if the tops are over 8 to 12 inches in length. If seedlings are 3 feet or more, they can be set with or without cutting back the tops. One-year-old seedlings are universally used, as 2-year stock is practically always too large to handle economically.
LARGE-SCALE PRODUCTION
An acre divided into beds 100 feet long and 4½ feet in width and separated by 18-inch paths, will have about 70 beds with an aggregate of 28,000 square feet of seeded bed. At the rate of 1,200 trees per 100 square feet of seeded bed there should be approximately 336,000 per acre. If there are only 8 seedlings instead of 12 per square foot, as may often happen, the production will be about 224,000 per acre. The common maximum is probably about 500,000, and the average probably about 300,000 per acre.
CARE OF NURSERY BEDS
The growing seedlings should be kept clean of weeds and given occasional cultivation. Except in the case of a real drought, it should not be necessary to water the beds. Medium-dry conditions will tend to develop desirable plants with small tops and large root systems. Any excess of rain or watering may result in too large stock, say from 2½ to 5 feet in height. Black locust withstands fairly dry conditions very well
