The first of several small office buildings to house nonprofit organizations interested in renewable natural resources will be started in September on the former Gilbert Grosvenor estate in the Pooks Hill area of Bethesda.

The start of the enclave for headquarters of groups interested in forests, wildlife, fish, water and plant life was made possible by a recent grant and a loan made to the Renewable Natural Resources Foundation, an umbrella group.

A $1 million grant was received from the Max C. Fleischmann Foundation to retire land loans and start development of a resources center for the consortium of professional societies. The 35-acre former home of the late Gilbert Grosvenor and his wife was purchased several years ago.

The mansion, now refurbished and usedas an office for the Society of american Foresters, will be preserved. So will the Grosvenor estate carriage house now used by the American Fisheries Society.

C. Gordon Fredine, executive director of the foundation, which owns the property with the Society of American Foresters, said that a $1.2 million tax-exempt loan -- from the Maryland Industrial Development Financing Administration through the First National Bank of Maryland -- has been obtained to begin construction of the first new office building.

Member organizations include the American Fisheries Society, Society of American Foresters, Ecological Society of America, the American Geophysical Union, the Wildlife Society, Society of Range Management, American Water Resources Association, the Institute of Ecology, American Association of Conservation information and Association of Interpretive Naturalists.