Observations on the growth performance, rooting behaviour and distribution of fine roots of five tree species viz., Bauhinia purpurea, Grewia optiva, Eucalyptus tereticornis, Leucaena leucocephala and Ougeinia oojeinensis (Family: Papilionaceae) are being presented here. Roots were exposed at the time of planting, 6 months, 16 months, and 28 months after planting. Total root weight and root volume were highest in Eucalyptus tereticornis and lowest in Bauhinia purpurea. Major part of the root system confined within 90-120 cm soil depth in case of Bauhinia purpurea, Grewia optiva and Leucaena leucocephala but Eucalyptus tereticorhis and Ougeinia oojeinensis strike their roots to deeper depths. Bauhiniapurpurea had its roots evenly distributed down to 120 cm. In general, the vertical distribution of fine roots (< 2 mm in diameter) of the five species indicate that more the depth, fewer the number of roots. The observations on soil binding capacity, indicated that Ougeinia oojeinensis had the maximum and Eucalyptus tereticornis had the minimum binding value. Due to leaf shading and other litter fall significant increase of nutrient components in soils under the tree canopies has been observed. The study indicates that bulk of the roots of the five tree species are found near the surface, but observation on soil moisture and nutrient content does not indicate variation under the tree canopies and in open, hence there may not be root competition in initial years of plantation.

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The effect of perennial mulches on moisture status, soil characteristics and on crop yields (maize-wheat rotation) was evaluated from 1986 through 1989 in a silty loam acidic soil (pH 5.6, PWP 11.4 & FC 25.6%) at the Research Farm of the Central Soil & Water Conservation Research & Training Institute, Dahra Dun. Mulch materials, comprised of leaves of Leucaena leucocephala, Eucalyptus hybrid, Shorea robusta, Broussonatia paprifera or Pueraria hirsuta (chopped) @ 4 t/ha were applied just after sowing of wheat and the residual effect of applied mulch was seen in kharif maize each year.The distribution of profile moisture revealed that at the time of sowing of wheat the soil water content did not differ with depth (0--90 cm). With the advancement of time, the magnitude of moisture distribution changed. At various crop growth stages the highest amount of water was found in the plots mulched with S. robusta followed by E. hybrid. All the mulch materials, except B. paprifera, lowered the soil pH, the maximum effect was noted with E. hybrid (pH reduced from 5.6 to 5.0). After three years, N and K content of soil were found to be greatest with the application of L. leucocephala whereas the highest P content was observed in B. paprifera mulched plots.The highest wheat grain yield (2.46 t/ha) was recorded with L. leucocephala and minimum under control (2.11 t/ha) which represents a gain of 11.7 per cent. Maximum maize grain yield (0.73 t/ha) was found in S. robusta mulched plots followed by L. leucocephala (0.63 t/ha) and the minimum in the control (0.51 t/ha).

Agroforestry systems, though at subsistence level are well established in Garhwal Himalayas. The farmers undertake cultivation of various crops, seasonal and biennials crops with trees all in mixtures on the same piece of land. Farm animals and poultry form an essential component of the systems. The intimate association of different species provides both subsistence and commercial products which give additional income to the farmer. The paper describes the general scenario of socio-economic condition and existing agroforestry practices and some suggestions for their improvement in the Garhwal Himalayas.

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