The grass family (botanical name: Gramineae or Poaceae) has about 8,000 species.

Grass is durable. It binds CO₂ from the air and releases oxygen again. Inone day a sports field captures up to 400 kg of CO₂ in the soil. This brings grass with forest and algae in the top 3 of largest CO₂ binders on earth.

With the production of meat and cereals, the grass family stands for about 95% of human food needs. Netherlands has about 1 million hectares of grassland.

Fresh grass consists of 80-90% water. The dry matter consists of 30% fiber, 20% proteins and amino acids, 15% oligosaccharides, 3% of complex and 9% simple sugars, 3% fat, 5% organic acids, and 10% minerals.
In case of frost, there is less phosphate available, which leads to some purple discoloration.
Normal grass has a dry matter content between 15 and 20%. Very rough, you can say that the grass height in cm corresponds to 1,000 kg of dry matter /ha.
In sunny, drying circumstances cut grass has a dry matter content of 40% after 1 day.

The vascular bundles (veins) consist mainly of for people indigestible cellulose. But herbivores can do this due to the micro -organisms in their gastro-intestinal tract. Bacteria or yeasts help those ruminants. The microbial digestion and fermentation in the stomachs (reticulum, rumen, and omasum) convert grass components into other compounds (e.g. lactic acid). In other herbivores (e.g. horse and elephant) this fermentation takes place in the colon.

The typical grass smell is caused by cis-3 -hexen- 1-ol. This is an organic compound having an alcohol group and a double binding in cis - configuration. This leaf alcohol is a colorless, oily liquid which attracts herbivorous insects. It also gives the taste of green tea.

Grass as a plants

Plants need light for photosynthesis. Grass can also continue to grow at night due to other chemical processes, as long as it is at least 6°C. The stem has long parts with nodes bearing the leaves. Above the nodes are the points at which growth of the new cells are formed.

The tillering zone is the stem portion on which nodes and other parts are very close together. In the axils of the scale-like leaves at the nodes new roots and stems arise: the tillering.
A feature of monocots is that each new leaf grows from the base of the plant, and not from the top. Hence grass is resistant to mowing and grazing (frequent topping).
If it is too short, close to the growing point, removed, it is experiencing discomfort.

The lower portion of the leaf, the leaf sheath, comprises the stem. Further, protruding part is called lamina. At the transition, you often see deformities characteristic for the species.
A young grass produces much leaf tissue and less stem and is therefore protein rich. An older plant invests in an inflorescence which needs a solid stem. The protein content is therefore lower.

A grass seed first makes temporary rootlets and stem. The tillering zone later makes permanent adventitious roots.

Grass roots shallow, the largest root mass is in the top 10 cm of soil.

Grass seeding
The T- sum (temperature sum) is sometimes used to determine the appropriate seed and fertilizer moments. It is the sum of average daily temperatures above 0°C from 1 January on. (E.g. coltsfoot flowers from T 180).

Sowing is done best 1 to 2 cm deep in early March - mid April, or even better from early August to late September. Lighter vegetated areas can be overseeded in the course of the year. The cattle hoofs the seeds in the soil.

Grass has its highest growth peak in April-May, and a smaller one in August-September. From November to March its keeps a winter rest. Let it not be less than 4-5 cm to go in to the winter.

Young grass roots up to 70 cm deep. That decreases after one year to 35 - 40cm, and then to 25-35 cm (or less). Of the living root mass 60 to 80% is in the top 5 cm.
Grasses are collectively strong enough to supplant other herbs.

Limiting trampling
Graze, especially in the fall, no more than 15 animals /ha. Put several different (food and water) troughs, and move them regularly. Exchange regularly plot. Make (10 meters) wide instead of narrow passage ports.

Trampling causes less activity of micro-organisms, earthworm and root penetration, soil drainage and air contend, a lower infiltration rate that reduces the absorption of rainfall, thus increasing runoff and erosion.

Thatch is not caused by the easily digestible snippets of mulching, but by surface roots and aboveground shoots of grass that digest difficult.
You can prevent thatch by improving the top layer of the soil (and the degradation organisms). This can be to increase the moisture content by the bottom of the thus by mowed grass higher.
Scarifying or aerate the turf can with a rake or machine. The blades comb thatch and pull narrow slits. You loosen the bottom layer again and remove each time (foolish?) a lot of organic material like moss and dead grass. Or scarifying has a net positive or a negative effect, the opinions are quite different. If possible let nature do its job, instead of working like a horse.
I estimate that scarification (as mulch mowing) first came since late 1980. However, the grass grew before even without much trouble.

For seven years "Centre Technique Horticole de Gembloux’ studied the effect of mowing: classical and removing grass versus mulching, where the grass remains fragmented. Mulch mowing is better. It inhibits the formation of felt (woolly rug between the blades of grass, so you have to scarify) and encourages soil life and the growth of microorganisms, so your lawn grows better. The grass grows better and more evenly than a classic green lawn mowed by the nitrogen from the clippings. A mulched lawn you have to fertilize less.

Sedge or reed grass (Carex) is best in moist soil and has 2,000 species and many hybrids belonging to the cyperaceae. Sedge has a triangular stem and no nodes, grasses have a round shaft with nodes.

How they put the sign “Forbidden walk” in the middle of the lawn?