Seeds of eleven woody species were exposed to 2.3 cm/wk of simulated sulfuric acid rain at pH values of 3.0, 3.5, or 4.0, or to a simulated control rain at approximately pH 5.6. All treatments also contained a neutral mixture of cations and anions based on concentrations reported for Hubbard Brook, N.H. Seeds or seedlings were subject to ambient conditions, except for precipitation. Ambient rainfall was excluded by a partial covering which allowed some dry deposition. Seeds were planted in winter, 1977; seedlings were harvested the following summer. The dry weights of the tops and roots of each seedling were recorded.