R. N. Sadhu , V. Kaul

Abstract

Seeds of Robinia pseudo-acacia were given different pretreatments to study their dormancy and germination pattern. Scarification of seeds with concentrated sulphuric acid and boiling water led to a good germination percentage and rate, with one minute pretreatment being optimum in both cases yielding 78 and 62 per cent germination respectively. Pretreatment for a longer duration resulted in damage to seeds thereby reducing the germination percentage. Rupturing the-seed coat at various sites yielded better results and removing a part of seed-coat at the radicular end yielded 100 per cent germination. Cold stratification of seeds at 5°C for varying length of time has no effect on dormancy of the seeds thereby suggesting that dormancy in Robinia pseudo-acacia seeds resides in the seed-coat which mainly interferes with water uptake of the seeds besides acting as a mechanical restraint to radical emergence.

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H. U. Dar , V. Kaul

Abstract

The Investigation reveals that both anthropogenic factors and the Himalayan black bear (Selenarctos thibetanus) are important factors influencing the natural regeneration of Quercus robus L., an exotic oak in Kashmir. Practically no regeneration has been observed at sites subjected to human disturbances or frequent visits of black bears. Suggestions are made to preserve and propagate the genus to maintain the oak wood population as per requirements.

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S. A. Bhat , V. Kaul

Abstract

The paper analyses the ecoogical status of three grasslands in Dachigam - Telbal Catchment, Kashmir. Study has revealed the presence of Themeda anathera - Chrysopogon echinulatus association on the slopes subject to light grazing, Poa stewartiana - Stipa sibirica on the slopes subject to moderate grazing and Cynodon dactylon - Bothriochloa pertusa association on the slopes subject to heavy gazing. The results further indicate that grazing reduces the vegetal cover significantly. Mild grazing is observed to increase the plant species diversity, richness and evenness at the first instance and with heavy grazing these parameters are observed to be reduced significantly. More of protection is also observed to bring slight decrease in the values of these parameters. Similarity between the grasslands is reported to be effected both qulitatively and quantitatively with varying degrees of protection/grazing. Possible causes of occurence of these changes in the grasslands under study are discussed. Many points are raised in the text of the paper for further research. Suggestions are made not to allow heavy grazing or comp1ete protection of grasslands as both of these treatments lead to homogenisation and decrease in plant diversity which is a great threat to the community as a whole.

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V. Kaul , R. Raina

Abstract

The paper records the phenological data of fifty most common trees and shrubs of Srinagar vis-a-vis the various seasons that the solar year is divided into. Most of the species show floral bud development in March, some in February and some others in April. The anthesis in majority of cases initiates in April and March. The fruiting als is pbasic and spreads from the last week of April or the first week of May to the onset of October. The low temperature and day-length of the winter seem to have a definite impact on the breaking of dormancy of both buds, foliar and floral, and seeds.

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