What is Mexican pine, where does it grow, and how many types of pine trees are there?

08/07/2021

How many species of pines are there in Mexico? This figure is still the subject of taxonomic discussion. Some authors claim that there are about 50, while others raise the figure to more than 70, but one thing is clear to all botanists: Mexico is the world's largest center of diversity of the genus Pinus.

Mexican pines generally grow in mountainous regions, between 1,500 and 3,000 meters above sea level. Together with other trees such as oyameles, oaks, and cypresses, they form the so-called coniferous forests, which cover about 17 million hectares of the national territory, that is, 3,370 million hectares of the forested area of the country.

Since the time of the conquest, pine forests have been affected, since the soils in which they thrive have been used for other purposes such as agriculture, livestock, and human settlements; moreover, fires, pests, and indiscriminate logging have destroyed many of them. In some cases, however, logging itself has helped the survival of these forests, since it has given rise to their reforestation in order to continue using them. The exploitation of pine forests produces great economic benefits; more than 60% of the pine species are commercially important and 80% of the country's forest products are obtained from pine-oak forests.

Both the hard pines of the Diploxylon subgroup and the soft pines of the Haploxylon subgroup have multiple uses. The wood of the soft pines is easy to work with, so it is used for the manufacture of furniture, housing, and boxes for packing agricultural products (avocados, melons, grapes, etc.). From the hard, more resinous pines, the resin is extracted and processed to obtain pitch, oils, and turpentine.

Pine trees are also used as firewood, in the production of charcoal, and to obtain cellulose to make paper. The bark is used to make compost that is added as a natural fertilizer to soils. The seeds of the piñon pines, the pine nuts, are edible and are used in many typical Mexican dishes and confectionery, and fetch very high prices. On the other hand, all the productive processes of exploitation of the pine forests are an important source of work.

The issue of forest harvesting

The traditional approach to forestry production processes has always been to guarantee the sustained yield of timber products, without taking into account biodiversity, aquifer recharge, carbon sequestration, soil maintenance, etc. Now we are talking about sustainable development that ensures the permanence of all the goods and services offered by forest ecosystems to society. The forestry sector has never been a priority, so it is necessary to implement a solid policy for the future.

Among the most common pine species in Mexico are Pinus oocarpa, Pinus pseudostrobus, Pinus montezumae, Pinus michoacana, Pinusengelmannii, Pinus durangensis, etc. And of the rarer species, we will mention, among others, Pinus rzedowskii, which has intermediate characteristics between the hard pines and the soft pines, which could provide some interesting answers to studies on the evolution of the genus.

Pine resin is one of the most important non-timber forest resources in Mexico.

To date, there are still many unknowns about the genus Pinus, but there is no doubt that to understand the mysteries of its evolution it will be necessary to have an in-depth knowledge of the Mexican species. More than 50% of the 90 to 120 species of pines that exist in the world are found in Mexico, which makes it the world record holder in terms of diversity. Such a distinguished place deserves respect. Is there a better tribute than trying to maintain it?

Pine species in danger of extinction

P. culminicola

P. maximartinezii

P. rzedowskii

P. pinceana

P. johannis

P. radiata (var. binata)

P. lagunae

P. jaliscana

P. nelsoni

By Emma Romeu, Source: CONABIO, Biodiversitas (2)