Pinus patula is an arboreal species better known as weeping pine, Mexican pine, red pine, candelabra pine or in Puerto Rico as gelecate pine. It is a gymnosperm of the Pinaceae family native to New World, Mexico. It is one of the most attractive pine species in nature.
The weeping pine is an exotic species that was introduced to South Africa from Mexico in 1907. It has good characteristics to be used in forestry practices. This Mexican pine has also established itself in New Zealand, Australia, India, Sri Lanka, Argentina, Brazil, Ecuador, Colombia, and Venezuela.
Male cones of the Mexican pine. Dick Culbert from Gibsons, BC, Canada
It is a fast growing pine species that has served to produce forest plantations, to counteract deforestation, for example in countries like Ecuador.
In these plantations, the vegetation cover offered by the weeping pine has facilitated the establishment of native species introduced in these forests. Pinus patula has been raised as a large-scale cash crop in Africa.
characteristics
Tree
They are typically trees that are 20-30 m tall, and some are up to 40 m tall. They have a cylindrical stem that can sometimes produce two or more stems, and are about 1.2 m in diameter. Likewise, the stems show apical dominance at an age of 30 years. The lateral bracts, more or less horizontal, sometimes tend to be arched.
The secondary twigs are arranged in a pendulum fashion. Stems are multinodal with 2 or more whorls per bract, or uninodal with only one whorl.
Leaves
The oocarpae subsection, to which this species of pine belongs, is characterized by species that tend to have three leaves per fascicle, but sometimes vary between two and five. The hypodermis consists of cells of different shapes. They also contain intermediate, rarely internal or septate, resin canals.
Particular trunk of P. patula. Krzysztof Ziarnek, Kenraiz
Needles can last from two to four years, in fascicles of three or four, sometimes two to 5. These needles are 15 to 30 cm long, and are generally 20 cm long. Its color is yellowish or dark green. The margin of the leaves is serrated with stomata present on all sides.
In general, the long, hanging bracts and needles make this tree a very graceful species and a very attractive tree. In P. patula, the epidermal cells of the leaves protrude so that the surface appears thoroughly tuberculated.
Cones
The cones or strobili, as their name indicates, are conical, and vary from subglobose to oval or sub-cylindrical shapes, more or less symmetrical and slightly oblique. This is the same as in P. patula, in other Californian and Mexican species such as P. insignis, P. tuberculata, and P. muricata.
The scales on the inner and outer side are uneven. The color of the cones is gray to light brown, reddish or dark brown and matte. The scales have spiny protrusions and open irregularly to release the seeds. The number of seeds ranges from 35 to 80 per cone.
Cones of P. patula. Dick Culbert from Gibsons, BC, Canada
Habitat and distribution
The weeping pine has an establishment range in Oaxaca in places where the annual rainfall is around 500 mm. However, in its natural habitat it can be found in locations with annual rainfall of 1000 to 2000 mm.
The temperature that favors its growth is between 10 and 40 ° C, being the one that grows the most at 30 ° C. For this reason, in the Andes, low temperatures are a limiting factor for its growth.
The altitude at which they best adapt is 1650 meters above sea level, and their growth declines below 1000 meters above sea level. It grows well in preferably acidic soils.
Its distribution is wide, it is found in Mexico, Central American and Caribbean countries and in many Latin American countries such as Argentina, Brazil, Ecuador, Colombia, and Venezuela.
On the African continent, it is practically distributed in most of its territory. Also, this pine is present in some Asian countries.
Mexican yellow pine. jacilluch
As an interesting fact, and as in most pines, its establishment in conjunction with the mycorrhizae allows the healthy growth of this gymnosperm. Therefore, the inoculation of the soil with mycorrhizal spores is a practice that is carried out at the time of the establishment of a forest of these pines.
The candelabrum pine, as it is also known, is sensitive to mechanical damage from the wind, because its root system is relatively short. It is also sensitive to drought and fire. Likewise, weeping pine is sensitive to damage caused by frost below 10 ° C.
Taxonomy
The most recent description of Pinus patula Schiede & Deppe is as follows:
- Kingdom: Plantae.
- Subkingdom: Viridiplantae.
- Superphylum: Embryophyta.
- Phylum: Tracheophyta.
- Class: Spermatopsida.
- Order: Pinales.
- Family. Pinaceae.
- Genus: Pinus.
- Species: P. patula (Schiede & Deppe 1831).
Similarly, some varieties have been found in Buenos Aires, Argentina, one of them named P. patula var. Zebrina, Milano (1948). For the interest of some farmers who have reproduced it vegetatively, it has been registered under the cultivar name "Zebrina".
Two other varieties of P. patula var. macrocarpa Marters, and P. patula var. stricta Benth, were referred to by P. greggii Engelm.
It has some synonyms, for example: P. subpatula, P. oocarpa var. ochoterenai, P. patula var. longipedunculata
Applications
The Mexican pine has been used for the construction industry, for the manufacture of boxes and roofs with the use of its logs. Also, this pine has been used to make poles for telephone wiring.
The Mexican pine has also been useful for the manufacture of pulp and paper, as well as in the production of wooden boards.
On the other hand, and in ecological terms, the weeping pine has been studied for the benefit that its coverage produces on the establishment of native and introduced plants for the recovery of forests, for example in countries like Ecuador.
Pests
Most of the pests that attack this species of pine are insects of the order Coleoptera (Scarabaeidae - Rutelinae, Chrysonelidae, Curculionidae) and Lepidoptera (Noctuidae, Tortricidae, Lasiocampidae), with a high number of Hemiptera, Hymenoptera, Isoptera and Orthoptera (Pyromoridae)).
In general, these pests cause defoliation at the level of seedlings and young leaves, and produce cuts in young roots and stems.
References
- Engelmann, G. 1880. Review of the genus Pinus, and description of Pinus elliottii. Transactions of The Academy Science of St. Louis. 4 (1): 1-29. Taken from: biodiversitylibrary.org
- Hansen, K., Lewis, J. and Chastagner, GA 2018. Compendium of Conifer Diseases. The American Phytopathological Society. 44 p.
- Wormald, TJ 1975. Pinus patula. Tropical Forestry Papers. 7: 1-172
- Aguirre, N., Günter, S., Weber, M., and Stimm, B. 2006. Enrichment of Pinus patula plantations with native species in southern Ecuador. Lyonia, 10 (1): 17-29.
- The Taxonomicon (2004-2019). Taxon: Species Pinus patula Schiede ex Schltdl. & Cham. (1831). Taken from: taxonomicon.taxonomy.nl