Walnut Tree (Juglans regia) Variety Classification, Cold Protection Methods and Key Cultivation Techniques
The walnut tree is also called the common walnut, and generally there are two varieties: wild hickory and the improved walnut produced by artificial grafting. The fruit of the walnut tree is one of the better-known nuts, and it can boost intelligence, nourish the brain and strengthen memory. So what are the classifications of walnut tree varieties? How do you carry out walnut tree cultivation techniques? What cold protection measures for walnut tree seedlings are there?
I. Classification of walnut tree varieties
1. Qiuzi walnut
The Qiuzi walnut is one of the wild walnuts, mainly concentrated in Northeast China, and what makes it different from other walnuts in appearance is that it has six ridges. The Qiuzi walnut is mainly used as a collectible walnut, belonging to the relatively low-end category of collectible walnuts; its price is a bit higher than that of eating walnuts, but lower than that of other varieties of collectible walnuts.
2. Ma walnut
The Ma walnut is a semi-wild walnut with many varieties, basically all collectible walnut varieties; unlike the Qiuzi walnut, the Ma walnut has very high collectible value and is very expensive. It is mainly produced in North China and the Hebei area.
3. Iron walnut
The iron walnut is a walnut type from the south; unlike the Qiuzi walnut, the surface of the iron walnut has a grain pattern similar to peanut skin. Its appearance is very close to the edible walnuts we commonly eat, so it gives unscrupulous sellers the opportunity to mix the genuine and the fake, passing off fake iron walnuts as the real thing; when buying, everyone should compare them carefully.
4. Cotton walnut
The cotton walnut is an edible-type walnut, mainly used for pressing and extracting walnut oil. The cotton walnut has very shallow surface grain patterns; unlike the iron walnut, its surface has no small pits and is relatively smooth, and its size is not large.
II. Walnut tree cultivation techniques
1. Walnut trees are generally harvested for seed between August and September, then undergo the procedures of peeling and air-drying, and finally are put into storage. By the following March, the seeds can be prepared in advance by soaking them in cold water for more than two days; after taking them out, mix them with sand and mud and pile them in a spot with direct sunlight. After that, keep watering them every day to provide a sufficiently moist environment. After about half a month the shells will begin to crack, and they can be selected daily for sowing.
2. Walnut grafting is generally carried out from March to April; around mid-March you can begin collecting scions, and the matching rootstock is best about 1.5cm in thickness. Walnut grafting does not easily survive, mainly because the preparation beforehand was not done properly. Before grafting, the roots need to “release water” within twelve hours, and the wound should be quickly wrapped and tied well.
III. Cold protection measures for walnut tree seedlings
1. Cold protection by hilling soil around walnut tree seedlings
Hilling soil for cold protection mainly means piling soil within a 30 cm range around the walnut tree seedlings, which can reinforce the soil protection at the roots and resist the cold in winter.
2. Cold protection by burying walnut tree seedlings in soil
Burying in soil for cold protection is aimed at walnut tree seedlings exposed outdoors; because winter temperatures are low, they cannot be fully brought indoors, so the entire tree body can be bent to the same side and covered with 40 cm of soil for cold protection.
3. Cold protection by whitewashing walnut tree seedlings
Whitewashing for cold protection is the most common method we use; after whitewashing, it mainly helps ease the temperature difference on the trunk. Whitewash formula ingredients: quicklime, clean water, salt. Mix and stir according to a 12:30:1 ratio.
The above is the walnut tree knowledge compiled for you by Tuliu.com; we hope it is helpful to you.