Williams College
OP-10: Landscape Management

Williams' grounds are divided in to several different types. While all are managed through IPM, the threshold for action on pests is different for each type. For example, the game play fields are expected to meet NCAA standards and therefore require the most maintenance, both in terms of mowing and cultural practices and input of chemicals when pests do appear, or as occasional preventive measures in previously infested areas. In contrast, the "common grounds" (most green space on campus) is managed with a very high tolerance for pests, and very little chemical input.

The goal for sustainable insect management is the same as weed management: to first use natural preventative techniques, then use insecticides sparingly and as effectively as possible. The primary cultural control for preventing insect infestation is core aerating to remove thatch that would help insects thrive.

When Williams replaces plant material on campus, we replace with native plant materials. All plant designs are reviewed and approved by the college's Horticulturist.

All grass clippings are left on the grounds during mowing. Other leafy waste from grounds keeping is transported to local farms for composting. Woody waste is burned at the local Department Public Works shed for heat. At times, wood chips are also taken to a local farm for composting.

We use pesticides as infrequently as possible. We just live with dandelions, rather than spraying them. When we do have to use pesticides, we usually use havlf the amount that is recommended. We don't use any insecticides other than a preventative for white grubs. We use fungicides as a preventative every 3-4 weeks from mid-June to the end of August.

We buy our mulch (double shredded bark mulch) from a lumber company in Ashfield Mass that makes mulch from their by-products from their lumber company. The fertilizer Williams College uses is organic - Nature Safe.

The college does very little irrigation. None of the practice fields, common grounds or meadow areas is irrigated. All of the water that these fields receive comes from rainwater. The only turf that is irrigated is on the game fields (Priority A). They are watered by permanent in-ground irrigation systems. The goal is to constantly maintain an inch of water per vertical foot of soil per week. To save time and money, this is only a rough estimate, evaluated by feeling soil samples and comparing to a chart to determine relative moisture. These fields are also visually monitored daily for moisture stress by looking for brown or wilting spots. The irrigation system is not set on a permanent timer schedule. It is only turned on if the water level is getting low or if a hot, dry day is predicted. This practice is important because the water that is used in the irrigation system comes from Williamstown’s potable water source. A benefit of only watering as necessary is that the game fields are irrigated to minimize the duration of leaf wetness. This means watering early enough in the day that the grass is not damp when night falls. Moisture encourages disease so minimizing leaf wetness discourages disease and reduces the need for preventative and curative pesticides.

Use sand and rock salt mix on roads and sidewalks. Roads are not sanded until needed. It is applied only after snow has been cleared. At entryways, we use just magnesium chloride which is easier on the sidewalk and grounds and reduces sand and contaminants entering the buildings. Magnesium chloride on the top deck of parking garage, due to the metal expansion joints. A sand / salt mixture reduces the amount of salt used. Catch basins are cleaned annually. Mechanical equipment is used to control the amount of material applied.