Saturday, January 7, 2012

Pyrus betulifolia: smaller pears World

It lives with the panda in bamboo forests

Pyrus betulifolia, called Tang Li in Chinese and Birchleaf pear in English, is a deciduous wild pear tree that lives in the leafy forests of northern and central China. Under optimal conditions for growth it can reach 10 meters high. Its leaves are protected from the predation by herbivores with stems modified as formidable thorns. Its narrow and extended leaves are very similar to those of the birch, though smaller. Hence comes the scientific name "betulifolia" meaning birch leaf.  

Small mature pears at the end of August. They have a round shape with a diameter ranging between 5 and 12 mm, a greenish-brown skin with white dots and a long stem 3 to 4 times longer than the fruit. Its small size is ideal for fruit-eating birds of China's forests, which they swallow whole and, after digesting the pulp, spit the seeds far of their mother-tree. I recommend to extend the photos with a double click to appreciate better the details.

The flesh of this small pear is juicy and surrounds three seeds. In the picture you can see that only one seed has matured. The other two may have been aborted by the absence of an effective cross-pollination, because in my garden the three specimens of Pyrus betulifolia are far apart. The flowers are visited by bees and it is likely that many seeds have been pollinated by pollen from Majorcan pear trees (San Juan and La Reina varieties), so that would give rise to hybrids.

This oriental pear tree was introduced in USA to be used like host of the worked pear trees by its resistance to pear decline disease and its tolerance to the limestone soil and the drought. Its affinity with the majority of varieties of pear tree is very good, especially with the oriental Nashí and Shandong pear trees, of yellow skin and Hosui, of brown skin. From the USA it passed to France and Italy where its promising qualities as host woke up a great interest among the growers. In 1960 they arrived to Spain some French and Italian trees, from which were selected some especially resistant clones to the drought and to the limestone earth.

Floral bud initiating the growth of the cocoons at the end of February. A vegetative bud is also seen that it begins to grow weeks after beginning the flowering and in the end of the stem a dangerous thorn of three centimeters. 

Small elongated leaves of Pyrus betulifolia a light living green. The petiole of the leaves is somewhat shorter than the blade. The new branch bark is whitish.

The dry leaves are used to prepare similar infusions to the tea. The fresh and dry fruits, chewed several times to the day, are used in natural medicine to alleviate the dry cough of the bronchitis, to smooth the throat in the acute and chronic faringitis and like astringents in the diarrhoea by their tannin wealth. 

In China Tang Li wine (Birchleaf pear wine) is prepared macerating 250 grams of dry fruits in a liter of rice wine during 10 days, stiring the mixture every day so that the flavor of the pears pass to the wine. In Japan they replace the rice wine by Japanese sake. 

Its small flowers of an immaculate target are very perfumed and in Majorca they are open at the end of winter, something later in colder regions. A fine thorn like a needle can be observed the left above that protects the flowers and the leaves of the snout of the herbivores.

 Gorgeous flower with its five petals white like the snow and its twenty stamens, four in the base of each petal, with pink anthers in the end of a long style. Like in the previous photo bifid pistil of a yellow clear color can be seen.

The fruits usually mature at the end of August and remain in the tree after the falling leaf to serve as food to the birds during the long months of the winter. It is a very beneficial association for both parts, a symbiosis. The pear tree feeds the birds that thus manage to survive the harsh winter and these give back to the favor dispersing its seeds more far possible so that they can colonize new territories.



5 comments:

  1. I didn't know the leaves can be used as medicinal tea. In the USA we have "Bradford Pear" and looks very similar.

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  2. Here is a great link with info:

    http://www.duke.edu/~cwcook/trees/pyca.html

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  3. Yes, it's very similar, but it is not the same. You can see the difference here:

    http://www.theplantlist.org/tpl/search?q=Pyrus

    Best Regards



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  4. What are the active constituents of the plant?

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  5. According to natural medicine, the leaves and fruits of this pear tree, like all trees of the genus Pyrus, have diuretic properties and the bark have anti-inflammatory and analgesic activity. I don´t know the name of the active chemical substances.

    Best regards.

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