Oak trees are mostly found in the northern hemisphere. The genus Quercus, has around 400 species which are either deciduous or evergreen in nature. This tree bears fruits in the form of nuts known as acorns. These are enclosed in hard structures called cupules that are cup-shaped. Fruits generally ripen between late August and September, however, the ripening can vary.
In the United States, collection of nuts is done in late September through November. Since it is difficult to locate acorns under the thick layers of litter in forests, it is better to search for a tree that is adjacent to lawns or parking lots. Gathering acorns becomes easier in such localities.
Storing the Acorns
There is danger of the fruits losing their vigor or germination capacity if they are dried out or heated up. Thus, care needs to be taken for their storage. Different types of oaks such as white oaks, chestnut, swamp oaks, etc., do not require storage. It is possible to plant them immediately; however, other species like the red oaks need a complete season for germination. Nuts are known to remain dormant during this period.
Since it is necessary to prevent fruits from drying up, they should be stored in polythene bags mixed with damp sawdust or peat. These bags are ideal because oxygen and carbon dioxide permeate them while moisture is restricted. They are then placed in refrigerators and a temperature of around 40 °F is maintained. Acorns of the red oak need to be refrigerated approximately for 42 days or 1000 hrs.
Planting Oak Tree Acorns
Since the white oak acorns don't undergo dormancy, they are planted immediately after collection. Red oaks are usually planted in April. The procedure of potting and transplanting for both the species remains the same.
Pots with a one-gallon capacity should be used for planting the acorns. They should provide proper drainage for any excess water. The soil in the container should be kept moist and well-aerated. Sowing should be done at a depth, that is half the width of a single acorn nut.
It should be done when the first set of leaves appear. There is a possibility of roots outgrowing the container and entering the soil present below. The hole prepared for transplanting the seedling should be twice as big as the container. While transplanting the seedling, care should be taken to maintain the root crown at the surface. The soil around the seedling should be properly tamped after watering.
The oak tree is considered a symbol of strength and endurance. It has been chosen as the national tree of as many as 12 countries, including the United States and England.