On the basis of ecology and forest type classification (Champion and Seth, 1968), the beautiful Himalaya’s many forests can be roughly divided into coniferous forests and broadleaf forests. The trees in both groups tend to be zoned by altitude, but there is some mixing of trees in the areas where their zones meet. In general, geology and soil type, the position of the snow line, and the exposure play important parts in how trees grow at different heights (Puri, 1960). In the western part of the Himalaya, the forests are mostly made up of conifers. They are put into five groups based on where they live, what they eat, and how much land they cover. Dogra (1999) puts deodar and chir pine in the same group because they are both widespread and grow in many places. Both trees grow over large areas in the Himalayas. Deodar grows at levels between 1200 and 3300 m from Afghanistan to Kurnauli in West Nepal, which is to the east. From Pakistan to Arunachal Pradesh, where the full power of the monsoon is felt, is the only place where the chir pine grows (Sahni, 1990). So, in the natural range of these two taxa in the Himalayas, deodar grows at a wide range of altitudes (1200–3000 m), while chir pine grows at a smaller range of altitudes (450–2300 m) (Champion and Seth, 1968). So, both taxa grow together in some places where their altitude ranges meet or are the same. However, in a natural distribution of these two taxa, chir pine rarely replaces deodar at the higher level of a mixed forest.
In general, deodar can handle colder weather better than chir wood. At the site where this work is taking place, chir pine grows on scarp slopes of quartzite next to deodar in the natural zone of deodar, but it also grows above it more often. Several early foresters were able to explain why the spread of taxa at this site is different from what would be expected based on their height. Taylor et al. (1936), based on analysis of soil profiles under several conifers including deodar (Cedrus deodara), blue pine (Pinus excelsa now Pinus wallichiana), spruce (Pinus morinda now Picea smithiana) and chir (Pinus longifolia now Pinus roxburghii) in the Kullu Forest division, concluded that the forest type in the studied region is broadly related to the degree of maturity of the soil. Puri (1949) thought that the type of rock in this area played a big part in where the conifer species were found. Puri (1949) and Negi (1986) almost had the same idea, which is that the structure and makeup of the rock below the surface has a big effect on the type of plants that grow on the surface. If not, this changed tree succession in this narrow belt could have spread to the rest of the Kulu valley, where the weather is mostly the same and the area is bigger. Fire also plays a big role in how deodar, blue pine, and chir pine are spread out in this area (Champion and Seth, 1968).
Dendroecology helps us figure out how the growth of trees is affected by both living and nonliving things, such as temperature. Tree-ring analysis done in other parts of the Himalayan region shows that chir pine (Bhattacharyya et al., 1988, Bhattacharyya et al., 1992, Shah, 2007, Brown et al., 2011) and deodar (Bhattacharyya et al., 1988, Yadav and Bhattacharyya, 1992, Yadav et al., 1997, Borgaonkar et al. As the features of the site are a big part of dating, it is important to look at the basic tree-ring features of the same species to figure out if trees at new sites can be dated or not. (La Marche et al., 1982) There are many cases where lost or fake rings make it impossible to date in some places, even though the species may be good for dating in other places.
This paper talks about how dendroecological study of deodar and chir pine from a new site in Kasol, Kullu,Kufri Western Himalaya, might work. The aim of the study was to find out why the deodar and chir pine at the study site were spread out in a way that was different from how conifers in the Himalayas usually grow.