Scientific name: (Melia azedaeach L.) Family: Neem, Neemaceae.　Alias: also known as neem tree, purple flower tree, neem date palm. Cui tree, Mori tree, neem jujube tree, fire jujube tree, flower heart tree, bitter spice tree, foreign flower Mori. Neem tree morphological characteristics: deciduous tree, up to 20 meters high. The crown is broad and flat-topped, and the branchlets are stout. The lenticels are numerous and obvious, and the leaves are alternate, 2 to 3 times odd-pinnate. Leaflets ovate to elliptic, apex acuminate, margin obtusely serrate, depth variable, base slightly oblique. Paniculate compound cymes axillary, flowers lavender, fragrant. Drupe subglobose, yellow when ripe, persistent branches, not falling through the winter. Flowering April to May, fruit ripening October to November. Bark dark brown, young branches with stellate hairs, shed immediately, old branches purple, with fine dotted lenticels. 2-pinnately compound leaves, alternate, 20-80 cm long; leaflets ovate to elliptic, 3-7 cm long, 2-3 cm wide, base broadly cuneate or rounded, apex long-acuminate, margins toothed, dark green above, light green below, stellate hairs when young, glabrous except for white hairs on the nerves a little later. Panicles axillary; flowers lavender, ca. 1 cm; calyx 5-lobed, lobes lanceolate, hairy on both surfaces; petals 5, spreading or reflexed, oblanceolate; androgynophore usually dark purple, ca. 7 mm. Drupe circular-ovoid or subglobose, ca. 3 cm, yellowish, 4-5-loculed, with 1 seed per locule. Flowering April to May. Fruiting period October to November. Neem Geographic distribution: Neem is an ancient tree species, in China in the 6th century A.D. "Qimin Yaojiao" there are neem growth characteristics and seedling afforestation records. Neem is widely distributed in China. Neem is widely distributed in China. It is cultivated in the south of the Yellow River Basin, East China and South China. It is naturally distributed in this region, but less cultivated. Mostly born on roadsides, foot of slopes, or planted next to houses, hedges. North to Hebei, south to Yunnan, Guangxi, west to Sichuan, are distributed.　Ecological habit: Strongly masculine tree, intolerant of shade, preferring warm climate, not strict on soil requirements. Resistant to moisture, wind, water and humidity, but in the waterlogged place is poor growth, intolerant of drought. Branches and tips grow fast, to the end of the growth period shoots are not yet fully mature, the top buds are easy to fall off, the tip of the tip is susceptible to frost damage. In the spring, the lower mature part of the main tip sprouts and grows again, thus forming the characteristic of much branching and short trunk. The main root is not obvious, the lateral root is developed, and the fibrous root is less, so it is strong in wind resistance, and thus the survival of large tree transplantation is poor. Young trees grow fast, short life, strong resistance to sulfur dioxide, etc., with the function of absorbing stagnant dust and killing bacteria.　Neem likes warm climate, light, intolerant of shade, vertical distribution in the altitude of 1000 meters below. It is not cold-tolerant, and young trees in North China are susceptible to frost damage, but large trees over 3 to 4 years old will be significantly more cold-resistant. The soil requirements are not strict, in the acidic, neutral, calcareous soil and salt content of 0.4% below the soil can grow, but to deep, fertile, moist soil is the most good. It is not drought tolerant and is afraid of waterlogging. The main root is not obvious, the fibrous root is developed, and there are many branches. Fast growth rate, in the environmental conditions of the place, 10 years old tree its trunk diameter can reach 30 centimeters. But its life span is a little short, 30 to 40 years that is the symptoms of senescence. Neem seedling cultivation: seed propagation is the main. The seeding rate is 25~40%, the seed weight is 550~830kg, 1200~1800 seeds per kg, and the germination rate is 60%~80%. Winter or early spring sowing can be, 15~20 kg of seed per mu, about 40~50 days before germination, mu yield 1.0~1.5 million seedlings, one-year seedlings 1.0~1.5 meters high.　Greening use: neem shape dashing, beautiful branches and leaves, flowers elegant and fragrant, and resistant to soot, pollution and can be sterilized. Therefore, it is suitable for shade trees, street trees, convalescent forest species, but also factory greening, four greening of good species.