Smith College, Northampton, Mass., is adding Treasury inflation-protected securities, real estate and timber to its $900 million endowment, said Jay Yoder, director of investments. The board approved the new investment policy last month, he added. The endowment expects to allocate 2% to 3% of total assets to a TIPS portfolio, which will be managed internally, Mr. Yoder said. Money for the TIPS portfolio will come from cutting back the endowments exposure to stocks and bonds. He declined to provide further information.