What does the seedling size D 1.36cm mean?

D 10- 12 "generally means that the ground diameter of seedlings is 10 ~ 12 cm.

Go to the northwest Miao network to find out, where there is rich knowledge.

The grade of seedlings is the main factor to determine its price, and the grade of seedlings is determined according to its own specifications. In the process of seedling trading, many people, especially those who have just entered the seedling industry, have a vague understanding of the size terms such as crown diameter, breast diameter and ground diameter of seedlings, which often leads to trading disputes. The author briefly introduces the common seedling size and terminology here for the reference of the people in the industry.

I. Terms and definitions of general specifications

1, plant height: refers to the vertical height from the surface to the top when plants grow normally.

2. Subbranch height (branch height): refers to the vertical height of the tree from the ground to the lowest branch point of the crown.

3. Bare stem height: refers to the height of the bare stem of Palmae from the surface to the lowest leaf sheath.

4. Irrigation height: the vertical height from the ground to the top of the normal growth of shrubs.

5.DBH: the diameter of the trunk at1.3m above the ground.

6. Crown diameter: the average of the maximum and minimum diameters of crown projection.

7. Crown diameter: the average value of the maximum and minimum diameters of shrub crown projection.

8. Base diameter: also known as ground diameter, refers to the diameter of the base of the seedling trunk at a distance of 0. 1 m from the surface.

9. Main vine length: also known as crown length and stem length, refers to the length of the main stem of climbing plants from the root to the top.

10, soil ball diameter: also known as ball diameter, refers to the diameter of the soil ball carried by the roots when seedlings are transplanted.

1 1. Mud ball thickness: Also known as the height of the mud ball, it is the height from the ground to the surface of the mud ball when the seedlings are transplanted.

In the actual seedling trading process, the above specifications and terms are often represented by corresponding symbols: for example, the height (plant height, irrigation height and bare stem height) is often represented by "H", for example, "H200-220" generally means that the height of seedlings is 200-220 cm; DBH is often expressed as "φ", for example, "φ 5 ~ 6" generally means that the DBH of seedlings is 5 ~ 6cm；; Crown width (crown diameter, canopy diameter) is usually represented by "P" (W is also useful). For example, "P80- 100" generally means that the crown width of seedlings is 80 ~100 cm; The base diameter is generally represented by "D", for example, "D 10- 12" generally means that the ground diameter of seedlings is10 ~12 cm; The length of the main vine is often expressed by "L".

Second, the application of seedling size terminology

Seedlings can usually be divided into trees, shrubs, palms and cycads, bamboo and woody vines. There are often many specifications of seedlings, but the specifications are arranged in order, the first is the main standard, and the second is the auxiliary standard. To determine the actual specifications of seedlings, we must first determine the main standards, and then determine the auxiliary standards.

1, trees

Arbor refers to a tree with tall trunk and obvious distinction between trunk and crown. For example, banyan, Lagerstroemia speciosa, Hainan peach, potted plant, flaming wood, face, orchid tree and mahogany are more common in the south. The specifications of trees can be expressed by DBH, height under branches, plant height, crown width, number of branches, diameter of soil balls, etc. "DBH" (φ) is the main specification standard in the market, but for smaller seedlings, especially annual seedlings, the price is often determined by the size of "DBH" (D) and "plant height" (H).

2. Shrubs

Shrubbery refers to those trees that have no obvious trunk and are in a tufted state. Plants are generally short, not more than 6 meters. Common shrubs in South China are Trifolium pratense, red velvet ball, Murraya murraya, African jasmine, azalea, safflower, cicada, oleander and so on. The specifications of shrubs can be expressed by irrigation height, crown diameter and soil ball diameter. At present, the main specification standard in the market is "irrigation height" (H), but the price of spherical seedlings is determined by the diameter of the ball, which is usually called "Peng diameter" (P), such as African jasmine ball and big red flower ball.

3. Palm trees and Cycas

The trunk of palm plants is cylindrical, often with old petioles and lower leaves, and the leaves grow at the top of the trunk. Common palm plants in southern China include nightshade, canary date, Middle Eastern date, king coconut, king leaf, beautiful Stipa, and Pukui. The specifications of palm plants and cycads can be expressed by basal diameter, plant height, bare stem height, crown width, number of branches (or leaves) and soil ball diameter. In the market, the bare stem height (H) is often used as the main specification for palms and cycads, while the base diameter (D, also called head diameter "T") and plant height (H) are often used as the main specifications for young trees.

4. Classification of common bamboo seedlings

Bamboo plants are tall and slender, and their specifications are often expressed by base diameter, number of branches per cluster, cutting height and soil ball diameter. "Base diameter" (d) and "number of branches per cluster" are usually used as the main specifications in the market.

5. Woody vines

Lianas are slender plants that can't stand upright and can only crawl on the ground or rely on other things to support upward climbing. They are called woody lianas in woody stems, such as honeysuckle and grapes. Woody lianas often express their specifications by ground diameter, main vine length, branch number and soil ball diameter. In the market, "ground diameter" (D) and "main vine length" (L) are often used as the main specifications.

It should be noted that although many seedling species use "H" to represent specifications, the concept may be different. For example, trees use "H" to represent "plant height", while palm trees use "H" to represent "bare dry height". Generally speaking, the factors that determine the price of trees are usually DBH, shrub height, crown width, bare stem height and seedling height.