Stephen Scott, Age 11, Of South Portland, Me,, for his question:

Why does the grass turn green in spring?

In many places, the meadows are hidden under wintery snow. There may be a few snowless spots, and in some places there is no winter snow at all. Then we notice that fields and lawns are matted with brown, dead stalks. Nothing it seems could reawaken this dead grass to life, but spring is full of miracles, and soon the grass is green again.

Now is the time when an alert boy casts a sharp eye at the lawns along the street. There will be grass to be cut and mowing money to be earned through the summer. It is pleasant to think of the jingling coins and the items they will buy. But if you want a successful, summer long lawn mowing contract, you need to know something about grass and how it grows.

There are some 5000 different grasses in the plant family gramineae. There may be half a dozen or more different turf grasses matted together in a lawn. Most of these grasses are similar to those cultivated in fields and the wild varieties that carpet the hills and valleys. All of them depend upon a sturdy root system which forms a matted network of threads mixed with the surface soil,

The sturdy root system of a turfy lawn, field or hillside can lie dormant through droughts and months of winter. But during these periods of hardship, it cannot support the green surface growth. The blades of grass whither and die, and the turf seems to be dead.

But spring comes around and thaws the frozen ground, melts the snow and pours down showers of warm rain, water seeps down and fills the pockets in the loose soil and grassy root systems, conditions are right for regrowth of new greenery. Many turf grasses spread by rootstocks. These modified stems are long and in jointed sections, each joint can sprout both root fibers to pierce into the soil and a shaft of greenery to grow up into the sunshine.

The green growth is a stem enfolded in pairs of leafy blades. It, too,grows in sections, in many turf grasses the first section turns brown when a new green section is added at the top, if you mow off the top greenery, you are left with a shaggy brown lawn which may stay brown all summer,

The pastures are cropped short by grazing cattle which is why many meadows stay grassy green through most of the summer, but when grasses are left to grow as they choose, they soon reach their proper height and produce modest flowers which become crops of dainty grass seeds. By summer, the grasses of the fields and waysides have lost their vibrant green, and they will not regain it until next spring coaxes forth new growth.