Shelter Belt Renovation

Driving through the state we’ve noticed a fair number of shelter belts with dead trees. If your trees are dying or your shelterbelt is old and in need of renovation, early fall is a good time to think about what to plant next spring. Soil Conservation District offices place orders with their suppliers starting in mid-October. The large number of dying pines and spruce in the state is a response to the wet weather in 2019.

Some things to consider before ordering trees include the cause of death. Did they have a disease or pest that killed them? Will this be an ongoing problem? Are they in a low lying area that has been too wet for the past couple of years? Is the soil type compatible with the species planted? What is the purpose? Is it for windbreak, livestock, wildlife, or soil erosion control?

Appropriate soil type for the trees planted is the most overlooked yet most critical component in successful tree plantings. Even old feed lots can be too high in nitrates and most SD soils are more acidic than many trees prefer. Doing a soil test or looking up soil types for your area at https://websoilsurvey.nrcs.usda.gov/app/ will help determine the best trees for a specific location. NRCS has a list that shows suitable soils and expected height for most shelterbelt species.

Nathan Kafer with the SD Department of Ag says that most conifers can only handle about a week of saturated soils or standing water before damage occurs. Weakened trees are more susceptible to already existing blights and fungus. The extent of the damage doesn’t show up until the next year.

Owen McElroy, Resource Biologist with SD Game Fish and Parks observed, “If you’re looking to benefit wildlife, stick to trees that are native to North America …those that attract the most caterpillar and sawfly larvae. It probably seems silly to plant something to attract bugs that feed on the tree, but they are what you need to start the food chain. Native trees have co-evolved with most of these species and tend to have no problems dealing with them.” Native trees such as burr oak and hackberry require special care with tubing for several years.

Many shelterbelts are 50 plus years old and need renovation. Kafer gave suggestions working on an older planting. Consider diversity, soil types and shade from existing trees when adding rows to the outside of a belt. Diversity is an important consideration as past experience with overplanting some species has shown. Consider varying species with compatible growth habits within a row.
Instead of planting new trees, allowing cattle to graze an area for 7-10 days can control competing brome grass while hoof action helps regenerate existing seeds. Siberian Elm and cedars will grow on their own if the grass is kept under control.

Shade tolerant junipers can replace dead trees within an existing planting. Scraggly shrub rows can be rejuvenated by cutting them back to ground level after blooming. They will rebound very well in a year or two.

Black Walnut and Black Cherry are both gaining in popularity but are toxic to livestock. Black Walnut can even kill other plants so companion trees need to be compatible. Other newer species that may work include Mongolian Oak, Siberian Larch, Northern Catalpa and White Pine. American Linden and Little Leaf Linden do well in urban setting in South Dakota. Meyer Spruce is an alternative to Colorado Blue Spruce. Another good resource for ideas of what to plant is the nursery your local Conservation District order from.

One other consideration when planting near a road is to check your county regulations regarding setback.

Planting trees is a big investment in terms of money and effort with long lasting consequences. Wise planning makes both the short- and long-term experience more satisfying.

Source: SDGC Newsletter