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Selective Pruning and Shade Seeding

VARYING AMOUNTS OF tree work are ongoing on practically every property, yet the removal and pruning of trees remains an emotional issue. Therefore, to avoid the inevitable backlash such emotions raise, the best time to do selective pruning or tree removal is in the winter or, for public grounds, during off-season.

Selective pruning, when care is taken not to ruin the shape of a tree or a shrub, will allow most trees to remain on-site and help to allow enough sunlight to filter through canopies for good turfgrass growth. Selective pruning also increases air circulation, thereby generally decreasing excess humidity and disease problems.

Selective thinning will allow some light through. A great rule of thumb is to remove no more than one-quarter of a tree’s foliage crown in a single pruning. Limbing-up of trees or raising the canopy of trees that branch to the ground has proven to be a very effective method of pruning without affecting the beauty of the surrounding landscape. In fact, it usually enhances views. This procedure prunes lower limbs back to the trunk, thus increasing airflow and decreasing shade.

Ultimately, however, one cannot prune enough to solve a serious shade issue. Some trees just need to be removed. In these cases, the problem is light quality, not light quantity. Most courses and properties that remove trees for the benefits of increased air circulation and sunlight will likely end up with some pretty great views, too. Removing trees alleviates the problems; the best way to avoid those problems is thoughtful planning. Watch where you plant your trees.

Morning light is critical for turfgrass. Avoid planting trees on the east and south sides of properties and in important turf locations like front- or backyards; planted there, trees will block the crucial morning sun so vital for optimum turfgrass growth. As increased sunlight helps turfgrass become hardier, healthier, and less prone to disease, the necessity for applications of fungicides, insecticides, and fertilizer will be reduced.

When planting turf in shaded areas, consider the needs of the grasses you choose. Fine-leaf fescues are considered the most shade tolerant of the cool-season grasses. They include creeping red fescue and chewings fescue. Turf-type tall fescue does well in moderate shade.

Fall seeding in shaded areas is preferred. The turf tends to be more successful as it enters the summer months due to better root systems and larger stored-food reserves.

Late fall fertilization of cool-season grasses is very beneficial in shaded environments. Late fall really is the only time of the year when grass beneath the trees can effectively utilize the nitrogen without tree competition for nutrients, light, and moisture. During spring and summer, trees with shallow fibrous root systems compete fiercely with turfgrass for moisture.

If all else fails, then the planting of shade-tolerant ground covers in heavily shaded areas is suggested. They look and work great.