How to Use Post-Emergence Herbicides on Chrysanthemum Seedlings and Precautions

The chrysanthemum is the third of China's top ten famous flowers. Besides being used to make tea, it is also a well-known Chinese medicinal herb, and growing it can bring good economic returns, but chrysanthemum fields are prone to weeds. So, which post-emergence herbicides can be used on chrysanthemum seedlings?

1. Which post-emergence herbicides can be used on chrysanthemum?

After chrysanthemum emergence, you can use 120 ml of 50% acetochlor emulsifiable concentrate, 150 ml of 50% napropamide wettable powder, 200 ml of 48% trifluralin emulsifiable concentrate or 100 ml of 24% oxyfluorfen emulsifiable concentrate, etc., diluted in 50 kg of water for spraying, and carry out soil sealing treatment.

2. Main varieties of chrysanthemum

1. Wild chrysanthemum

Wild chrysanthemum is a perennial herb, 0.25-1 m tall, with long or short underground stolons. The stems and branches are sparsely hairy, with slightly more or much more hair on the upper part and inflorescence branches. The basal leaves and lower leaves fall off at flowering time. The middle stem leaves are ovate, long-ovate or elliptic-ovate, pinnately parted, shallowly lobed, or indistinctly divided with shallow serrations on the margins. The petiole base has no auricle or has divided leaf auricles. Both surfaces are the same color or nearly the same color, light green. The capitulum is 1.5-2.5 cm in diameter, mostly arranged in loose corymbose panicles at the top of stems and branches, or a few arranged in corymbs at the stem apex. The involucral bracts are about 5 layers; the outer layer is ovate or ovate-triangular, the middle layer is ovate, and the inner layer is long-elliptic, 11 mm long. The margins of all bracts are white or brown broadly membranous, with obtuse or rounded tips. The ligulate flowers are yellow, with entire tips or 2-3 teeth. The achene is 1.5-1.8 mm long. The flowering period is June-November.

2. Sweet chrysanthemum

Sweet chrysanthemum is a perennial herb, 0.3-1.5 m tall, with underground stolons. The stem is erect, mostly branched from the middle upward, or only the upper part has corymbose inflorescence branches. The basal and lower leaves fall off at flowering time. The middle stem leaves are ovate, broadly ovate or elliptic-ovate. They are bipinnately divided. All leaves are the same color or nearly the same color on both surfaces. The petiole base has divided leaf auricles or no auricles. The capitula are usually numerous and arranged in loose or slightly dense compound corymbs at the top of stems and branches. The involucre is disc-shaped, with about 5 layers of involucral bracts. The middle and inner layers are ovate, long-elliptic to oblanceolate, and the tips of all bracts are rounded, with white or light brown membranous margins. The ligulate flowers are yellow, the ligules are elliptic, and the tips are entire or have 2-3 indistinct tooth divisions. The achene is 1.2-1.5 mm long. The flowering and fruiting period is May-November.

3. Small red chrysanthemum

Small red chrysanthemum is a perennial herb, 15-60 cm tall, with underground creeping rhizomes. The stem is erect or curved at the base, branched from the base or middle, but usually only with corymbose inflorescence branches at the stem apex. The middle stem leaves are reniform, semicircular, nearly round or broadly ovate, usually 3-5 palmately or palmately pinnately shallowly lobed or half-lobed, and the margins of all lobes have obtuse teeth, sharp teeth or bristle-like sharp teeth. The root leaves and lower stem leaves are the same shape as the middle stem leaves, but smaller; the capitula are few (about 3) to many (about 12), arranged in loose corymbs at the top of stems and branches, rarely solitary at the stem apex. The involucre is disc-shaped; the involucral bracts are 4-5 layers. The margins of all bracts are white or brown membranous. The ligulate flowers are white, pink or purple, and the ligules are long with 2-3 tooth divisions at the tip. The achene is 2 mm long, obliquely truncate at the tip, narrowed below, with 4-6 veined ribs. The flowering and fruiting period is July-October.

Because chrysanthemums are mostly used for tea and medicine, and herbicides are generally somewhat toxic, during cultivation, when there are not many weeds in the field, try to use a hoe to remove weeds.