Grass Flashcards
(17 cards)
what is the importance of grass?
Grass is extremely important to most people’s lives, whether they know it or not. For one thing, grass is a major food source all over the world. Rice, corn and oats come from grass plants, for example, and most livestock animals feed primarily on grasses. In some parts of the world, people use grass plants in construction (bamboo is a grass, for example), and wherever it grows, grass plays a vital role in curbingerosion. Grass is also used to make sugar, liquor, bread and plastics, among many other things.
what are the parts of the grass??
Grass stems, called culms, grow up from the base of the plant (thecrown). In most grass species, the culms are hollow and rigid, except at the nodes – joints that join stem segments together.
Narrow leaves extend out from the culms, above each node. The leaves alternate in direction. That is, if the first leaf on a culm grows to the right, the second leaf will grow to left and the third leaf will grow to the right and so on.
The lower part of the leaf is called the sheath, and the upper part is called the blade. In most grasses, aligule surrounds the connection between the sheath and the blade. A ligule can take the form of a thin membrane or a fringe of hair-like projections.
Is grass like leaves? explain?
Like the leaves on a tree, grass leaves serve to collect energy from sunlight through photosynthesis. The photosynthesizing chlorophyll in the leaf gives grass its green color.
How does grass reproduce?
There are two major methods of reproduction in grasses. Some grasses have additional stems that grow sideways, either below ground or just above it. Stems that creep along the ground are called stolons, and stems that grow below ground are called rhizomes. Grasses use stolons and rhizomes to reach out and establish new grass culms. The stoleon or rhizome nurtures the new plant until it is strong enough to survive on its own.
Does grass have flowers?
Grasses also have flowers. The small flowers in most grass species are known as florets. Florets grow together in small groups called spikelets, which collectively form inflorescences. Flowers produce the spores that pollinate other flowers, which produce seeds. With any luck, some of the seeds will grow new healthy grass plants
In some grasses, such as corn, the stem and the flowering part of the plant are obvious. But in lawn grasses, the long thin leaves overshadow the other elements of the plant. Unless you’re up close, all you see is green stalks.
What 3 things does grass need to live?
What 3 things destruct grass?
Additionally, it needs be largely free of destructive elements, namely:
Weeds
Disease
Bugs
Soil. its importance, how to improve, and how it should be.
No amount of water and sunlight will make your lawn luscious and green if you have poor soil, so this is a good place to start.
A grass plant’s backbone is its root system. The roots soak up water, collect nutrients, anchor the plant and, in some species, spread out to grow new plants. A plant can only do these things effectively if the soil is right.
The soil needs to be loose enough that the grass roots can spread easily, absorbent enough that it will collect water and rich enough that it can provide the plant with nutrients. Roots also need a certain amount of circulating air, which means the soil can’t be too compact.
Ideally, you want loam – soil that has roughly equal amounts of silt, sand and clay (a “perfect” loam is about 40 percent silt, 40 percent sand and only 20 percent clay). Loam is fairly loose, but it has enough clay to absorb water effectively. Check out this page for a simple soil content test.
The soil’s pH rating is also important. This rating tells you the relative acidity and alkalinity of the soil (this page explains the concept). The ideal pH level is around 6.5 or 7, but levels vary between different grass species and climate conditions. You can find out your soil’s pH level with a home test or a professional test.
If you need to substantially increase the acid level, add sulfur. If you want to reduce the acid level, add lime (this page will give you the details).
To improve your soil, you can amend it with topsoil, compost or fertilizer.
Picking the Right Grass and Planting It
To establish a beautiful lawn, you need to choose an appropriate type of grass. There are two major factors in this decision:
Your local climate (average rainfall, heat, etc.)
The amount of sunlight your lawn gets
Cool-season grasses, such as Kentucky Bluegrass, hold up well to cold winters, but don’t do well in very hot weather. Warm-season grasses, such as Bermuda grass, love heat and sunlight. Commercial grass seed is usually a mixture or a blend of species. Mixtures are combinations of different types of grass. The various species all have different strengths and weaknesses, so collectively they hold up to just about anything. Blends are combinations of different varieties of the same type of grass. Blends are not as adaptable as mixtures, but they are generally more attractive because of their uniformity.
Most grass species need direct sunlight several hours a day to thrive, but you can seed heartier grass that does well in the shade. If your lawn is completely covered in shade, consider another sort of ground cover.
It’s also important to pick a species that does well with the amount of water in your area. “Water-loving” grass species will do terribly in drought-prone areas, and some grasses develop fungal disease in very wet areas.
Additionally, consider how you’ll treat the grass. Some grasses hold up to heavy traffic and some don’t. If you have kids and outdoor pets, you definitely need a resilient mixture.
Planting Grass
To seed, first mix any topsoil, fertilizer or compost into your existing soil using a rotary tiller.
Then use a rake or board scraper to level the soil. This minimizes bumps and holes, which make mowing more difficult.
Next, scatter the seed, either by hand or with a mechanical spreader. The seed bag should tell you roughly how many seeds to use in a given area.
Compact the seeds with a lawn roller.
Rake the seeded area to lightly cover about half the seeds with soil.
Cover the lawn with a little bit of mulching material, such as straw.
Soak the seeded area and water regularly until the grass starts to come in.
Sodding is much more expensive than seeding, but you get instant results. With sodding, you can go from an anemic, patchy lawn to a rich green lawn in a day, whereas it may take years for a seeded lawn to grow in completely.
Sod arrives in rolled-up rectangular chunks, about an inch thick. Before you have the sod delivered, you should prepare the soil in the same way you would for seeding. All you have to do when the sod arrives is lay it out over the soil in straight rows. Stagger the sod chunks like you would stagger bricks in a wall. Fill in any gaps between the sod pieces with soil, compact the sod with a lawn roller and you’re done. Water the sod regularly until it is well established. It’s a good idea not to walk on the sod at first.
Grass sprigs (individual grass plants) and plugs (small sections of soil and grass) are a huge mail-order business. You specify the area of your lawn, and the company sends you the right number of live grass plants. Planting sprigs and plugs gets faster results than seeding, but it is more expensive and takes more work.
To plant sprigs and plugs, prepare the soil just like you were seeding or sodding. Then dig regularly spaced holes (6 to 12 inches / 15 to 30 cm apart, depending on the grass species), fill them with water and insert the plants. Fill in loose soil around the plants and press them into the ground. You have to water regularly and keep weeds at bay while the plants’ roots spread in the soil. In mail-order grass, such as Zoysia, the stolens branch out quickly to grow new grass plants.
Watering
Watering is simple. The general rule is to water heavily, when the lawn really needs it, rather than watering lightly more frequently. If you water lightly, the water won’t make it down into the soil so it won’t do much good. You should water enough to soak 6 to 8 inches (15 to 20 cm) deep, encouraging the roots to grow deep into the ground. Watering recommendations vary between different soil types, but as a general rule, water until there is about an inch of water (2.5 cm) over the ground surface.
Water as soon as the grass starts to dry out. Its color will change from green to bluish grey, and it will lose some of its bounce. If the grass doesn’t spring back a few seconds after you step on it, it needs water. The best time to water is in the early morning; the water won’t evaporate as easily as in the afternoon, and it will cool the lawn down as temperatures start to climb.
Mowing
Mowing reduces the workload on a grass plant’s root system. A large culm above-ground requires more water and nutrients from underground. It’s easier for the roots to provide for the plant if the culm is smaller. Mowing also encourages the grass plant to expand. When the blades cut down the leaves, the plant has to grow new leaves to absorb sunlight. This helps build a thicker, heavier lawn, which is more resistant to weeds and disease.
It’s best to mow frequently during the growing season. The rule of thumb is to never cut off more than a third of the grass plant at once – it’s bad for the plant to lose a lot of its photosynthesizing ability suddenly. One common mowing mistake is cutting the grass too short. It’s best to keep cool-season grasses at about 3 inches (7.5 cm) high or taller, and most warm-season grasses do well at about 2 or 2.5 inches (5 to 6.5 cm) high. You may want to vary the mowing height throughout the year. In fall, winter and spring, you can mow closer because temperatures are cool and water is more abundant. In the summer, let the grass grow longer. The shade will help cool the soil.
Lawn care experts recommend varying your mowing pattern. That is, push the mower north and south one week and east and west the next week. Sharpen your mower blades a couple of times a year to ensure a healthy, clean cut. If you have a mulching mower, you can leave the clippings on the lawn to help fertilize the grass.
Fertilizing
Aerating
When soil gets compacted – from foot traffic, mowing and the like – oxygen can’t reach the microbes that break down organic matter to enrich the soil. To keep your lawn healthy, it’s a good idea to aerate it periodically – to open up the compacted soil.
Manual and power core-aerators remove narrow sections of soil to form shallow holes. Air, water and organic material spread into the ground through the holes, revitalizing the soil. If heavy traffic compacts your lawn severely, it’s best to aerate it every spring or fall.
In any lawn, thatch material collects around the base of the grass plants. Thatch is not made up of mowed grass clippings, as is commonly believed. Clippings usually break down in a week or so. Thatch is actually made up of culms and crowns that have died naturally.
A small amount of thatch helps conserve water in the soil by blocking evaporation, but heavy thatch build-up (more than a quarter-inch / 6 mm thick) keeps air and water from ever reaching the soil. If there’s too much thatch on your lawn, rake it up or rent a power de-thatcher.
Weeding is an ongoing process, but it shouldn’t take much time once you establish a healthy lawn. Grass, especially modern mixtures, is extremely competitive and will crowd out most weeds itself. If a lot of weeds do pop up, take it as a sign that your grass is weaker than it should be. This could mean your soil is deficient or water-logged, or it could mean you’re cutting the grass too short.
Weeds will also pop up in a healthy lawn, of course. For the most part, this isn’t anything to worry about. Almost all lawns have weeds, and they don’t do much harm in small numbers. Simply pull up any weeds that detract from the lawn’s appearance. If you have a larger weed problem, spray the individual weeds with a low-toxicity herbicide. Don’t spray the entire lawn unless you have weeds throughout.
Pest Control
Pest control is similar to weed control. If you have a healthy, thriving lawn, you shouldn’t have to worry about it. Bugs will make their home in your lawn, but they won’t be able to damage the grass much.
From time to time, however, bugs may destroy some of your grass. You can treat infestations by spraying insecticide or certain bacteria (namely, Bacillus thuringiensis, or Bt). Only use insecticides that kill harmful insects specifically. Ants and spiders prey on lawn pests, so you certainly want to keep them around.
