Galinsoga quadriradiata is a species of flowering plant in the daisy family which is known by several common names, including shaggy soldier, Peruvian daisy, hairy galinsoga, and fringed quickweed. G. quadriradiata is a fast-growing annual herb with the capacity to invade agricultural and other disturbed areas in most temperate and subtropical regions of the world.
It is highly competitive and can spread quickly, often being the dominant species in a field. It is causing considerable economic impact in cropping systems, greenhouses, gardens and nurseries. Its presence may reduce yields up to 10-50% in fields planted with vegetables and crops areas. Hairy galinsoga is considered a weed throughout its native and introduced range.
Botanical description.
- Roots.
The roots form a fibrous root system.
- Leaves.
Leaves are up to 2½ inches long and 2 inches wide, coarsely toothed, sparsely to densely hairy, with a pointed tip and somewhat rounded or tapering base, oppositely attached. There are 3 distinct veins radiating from the base of the leaf. Leaf stalks are up to 1½ inches long near the base of the plant; becoming shorter as leaves ascend the stem; leaves in the upper plant are stalk-less or nearly so.
- Stem.
Stems are densely hairy and heavily branched with a height of up to 60cm.
- Flowers.
Flowers are at the end of hairy stalks arising from the leaf axils in the upper plant and at the tips of branching stems. Individual flowers are about ¼ inch across with 4 to 8 (usually 5) white rays (petals). The center disk flowers are golden yellow.
- Fruit.
Both the ray and disk flowers produce a dry seed, with 5 or more narrow scales attached at the tip, each scale fringed around the edges and with an awn at the tip.
Dispersal
It can be dispersed by wind, animals, or sometimes water in addition to the hairy nature, which assists in wind dispersal, achenes are covered with short stiff hairs that may cling to the fur of animals.
Dispersal by human activities, such as movement of soil or plants can be very important in the dispersal of this species. The most effective means of dispersal is believed to be seedlings inadvertently grown in nurseries or commercial greenhouses.
Environment requirement.
Quick weed is adapted to warm climates and heavy nitrogen rich and clayey soils and requires a PH range of 5-7.4. An average rainfall range of between 600-1200mm which is evenly distributed throughout the season favors its growth. Requires an optimum temperature of between 18-27°C.
Habitat
In much of its introduced range, it can be found in gardens, greenhouses, agricultural lands, roadsides, railways, and other disturbed areas, essentially in association with any form of human development.
Crops mostly affected by quick weed include:-
- Maize.
- Wheat.
- Vegetables.
- Onions
- Carrots etc.
Disadvantages of the weed in cropped areas.
- Its presence reduces yields by about 10-50%.
- It acts as an alternative host for many insects, viruses and nematodes which affect crop species.
- Takes up nutrients that are essential for cultivated crops.
- Its high leaf surface area can shade out cultivated plants.
- It leads to high cost of production.
- Results to blockage of drainage channels.
Greenlife solutions for the control of Quick weed.
This proves to be the most effective way of controlling the weed by the use of chemicals such as 2, 4-D, Paraquat and Glyphosate.
- At Greenlife we provide:
WEMBE 200 SL a non-selective post emergence herbicide, to clear Annual and perennial grasses and broad leaved (Quick weed) weeds and any other weed in the field including difficult weeds. Use during land preparation to clear all weeds.
Rate of use: 3.0Litres per Hectare (300ml in 20L) - CATAPULT 480 SL a non-selective Post emergence herbicide which controls Annual and perennial grasses and broad leaved (Quick weed) weeds. Use CATAPULT 480 SL during Land Preparation to clear all weeds.
Rate of Use: 2.0Litres per Hectare (250ml in 20L) - KEEPWATCH 450 CS
Selective Pre-emergence herbicide which controls Annual grasses and broad leaved (Quick weed) weeds on Maize, Wheat, Rice, Barley and Sugarcane. Apply immediately after sowing/planting but before it emerges. Ensure soil is well moist.
Rate of Use: 3.0 Litres per Hectare (300ml in 20L) - COMMANDER 240 EC
(Onion family-Selective early post emergence or Post transplant herbicide, 2-14 days after transplanting and Brassica family-Selective Pre emergence or Pre transplant herbicide, 2 days on well prepared bed before transplanting) on Onions, Garlic, Cabbages and Broccoli to control Annual grasses and broad leaved (Quick Weed) weeds.
Rate of Use: 1.0Litres per Hectare (50ml in 20L) - HOTLINE 450 SC
Non selective pre-emergence herbicide which controls Annual grasses and broad leaved (Quick Weed) weeds on French beans, Carrots, Baby corn, Coriander and Onions. Should be applied when soil is well moist.
Rate of Use: 1.0 Litres per Hectare (50ml in 20L)
