There may be no need for preparation of your chosen site. On the other hand, site preparation as intensive as land clearing with a bulldozer and spraying with herbicide may be required. You should ask yourself: How easy will the site be to plant? How will I control weeds?
The amount of site preparation necessary will be influenced by the planting method. Machine-planting of seedlings or hand-planting of either seeds or seedlings are the choices. Usually the amount of acreage to be planted is the controlling factor for choice of planting method. Should you decide to plant by machine, consider accessibility and obstacles that restrict planting machinery?
An important part of site preparation is weed control. Black walnut is a very intolerant species and does not compete well for moisture and nutrients. Competition from other trees or under story plants can reduce growth significantly or even result in plantation failure.Because trees are often planted on old row-crop land, the site will naturally have unwanted grasses and weeds. Both chemical and mechanical means are available for weed control. Use them independently or in combination to control most problem weeds. Chemical weed control is usually most effective. A combination of pre-emergence and post-emergence herbicides is preferred.
Whether you decide to plant seedlings or seeds, know the source. They must be compatible with your planting region for the plantation to grow well. Arkansas, Kentucky, Louisiana, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, and Virginia have state-operated tree nurseries which sell seedlings to landowners.Some private nurseries have black walnut seedlings. Check stratification and germination before purchasing seeds. Help in identifying seed and seedling sources is available from your county forester or Extension agent. Some genetically improved seed sources exist for black walnut seeds and seedlings. However, the price is usually high. Not enough data exists on black walnut to project additional profits from improved seed or seedlings, but other species have shown dramatic yield increases.Consider your objectives when deciding whether to use improved seed and carefully examine the claims of the supplier before using these sources. Space the trees according to the products of the plantation. Wide initial spacing with 134 or less trees per acre should be chosen if your main objective is nut production. Narrow initial spacing with more trees per acre should be chosen if your main objective is lumber and veneer production. If you plan to grow crops between trees during the first few years, spacing should be 40 by 10 feet to 40 by 20 feet.