Magazine - Weed of the week-Broadleaf Plantain

By Laurence Gale MSc in Consultancy on 11th Mar 2004 13:00

Weed of the Week: Plantago Major (Broadleaf plantain)

By Laurence Gale

What is a weed? By definition a weed is a plant that is growing in the wrong place. Weeds take valuable space, water, sunlight and nutrients that may otherwise be accessible to important crops, in our case turf grasses. Weeds not only compete for these resources they can disfigure and cause problems to playing surfaces.

Weeds are very good competitors and take advantage of any opportunities to colonise turf situations, particularly when the sward is under stress and weak, leaving bare soil areas for weeds to populate. Weeds have many mechanisms and characteristics that enable them to do this, having thick waxy cuticle leaves that can be resistant to some chemicals, fast reproduction methods, the ability to reseed in 6 week cycles and deep tap roots enabling the weed to survive in compacted dry ground conditions.

Weeds have one of three life cycles: annual; biennial or perennial.

• Annual weeds: Live for a single season. These weeds germinate from seed in the spring or summer, flower and then die.
• Biennial weeds: Live for two seasons. During the first growing season, these weeds remain in a vegetative stage and, in the following year, produce flowers, set seed and die.
• Perennial weeds: Live for multiple seasons and flower more than once. Perennial structures (rhizomes, stolons, crowns, entire plants or roots) survive from year to year.

Some weeds may be harmful to the environment or noxious to your regional ecology. For example Japanese Knot weed (Fallopia Japonica) is fast becoming a major weed problem on road side verges and urban landscape areas, a very difficult weed to eradicate. It is very important to recognise weeds and seek effective controls methods to eradicate them from our facilities.

Weeds can also be used as an indicator of soil conditions. For example, knotweed and plantains both indicate soil compaction because they can maintain adequate root respiration at lower oxygen diffusion levels than other plants. Different weeds tolerate different soil conditions, some are alkaline loving and others acid loving. Getting to understand and recognise the physiology of these plants will help you become better turfgrass managers.

This weeks weed is: Plantago Major (Broadleaf plantain)

Scientific name Family Life cycle	Plantago Major L. Plantaginaceae Perennial
Form / Appearance	Forms a rosette of rounded ribbed leaves with flower spikes.
Roots	Roots are fibrous and shallow.
Flowers	The flower is formed on a spike, flowers June-October.
Leaves	The leaves are broad-oval, pubescent or smooth, and dark green. The petioles are often purplish. The leaf margins entire or wavy, and the veins are prominent and parallel.
Reproductive method	From Seed. The flower stalks bear densely packed greenish white flowers each of which will become a seedpod containing 10 to 20 seeds. When the seeds are mature, the seedpods splits releasing the seed to the ground. Seed germination occurs at or very near the soil surface. The seed will germinate when soil moisture is adequate and soil temperatures rise.
Habitat	The main growth period for broadleaf plantain is from June through September. Plantains are a good indicator of compacted soils and can tolerate dry conditions. Plantains like alkaline soils.
Miscellaneous info	Plantains are used as medicinal remedies by herbalists, it can be used to heal sores, wounds and bruises. taken as tea internally to treat eczema and skin disorders and is well known for its ability to soothe urinary tract infections and ease dry coughs.
Cultural Control	Broadleaf plantain can be mechanically or physically removed. Care should be taken to assure that all roots are thoroughly removed. Close mowing prevents seed head formation and maintaining a dense sward will deter or prevent plantains from establishing. Good turf density is important as broadleaf plantain competes by shading other plant species with its broad rosette of leaves. Good soil fertility is essential, whilst maintaining a soil pH of 6.5 to 7.
Chemical Control	Apply selective broadleaf herbicides when plant growth is active. There are a number of products available for controlling broad leaf weeds in established turf. These chemicals are best used when the weeds are actively growing, usually between April-October. Tritox (Contains 178g/L (16.2%w/w) MCPA 54.g/L(4.9%w/w) mecoprop-p and 15g/L (1.4%w/w) dicamba and potassium salts. Scotts. Intrepid 2. (Contains 20.8g/L dicamba,166g/L dichlorprop-p ans 166.5g/L MCPA). Scotts. Greenor. (Contains: 40g/L fluroxypyr, 20g/L clopyralid and 200g/L MCPA). Rigby Taylor. Bastion T. (Contains: 72g/L fluroxypyr and 300g/L mecoprop-p ). Rigby Taylor. Dormone (Contains 465g/L2,4-D(38.1%w/w) as the diethanolamine salt). A herbicide which can be used near water. Bayer Environmental Science. Supertox 30 (Contains 95g/L (8.8%w/w) mecoprop-p and 93.5g/L(8.7%w/w) as the diethanolamine salts). Bayer Environmental Science. These herbicides are usually applied as a liquid using watering cans, knapsack sprayers and vehicle mounted sprayers. Ensure you follow manufacturer's directions, health & safety and product data sheets, and comply with COSHH regulations, when using these chemicals.

Read more articles in Consultancy, by Laurence Gale MSc or from March 2004.