There needs to be real strong, sustained grass roots pressure if change is to take place.

He also measured 'the force of the sap' or root pressure.

The water will accumulate in the plant, creating a slight root pressure.

Root pressure is often high in some deciduous trees before they leaf out.

Root pressure is studied by removing the shoot of a plant near the soil level.

Root pressure may be important in refilling the xylem vessels.

However, in some species vessels refill without root pressure.

Root pressure provides the impetus for this flow, rather than transpirational pull.

Root pressure is highest in the morning before the stomata open and allow transpiration to begin.

For plants less than 50 cm tall, root pressure can be sufficient to redissolve air.

It is driven in by capillary action and in some plants root pressure.

If a pressure gauge is attached to the cut stem, the root pressure can be measured.

In 1880 he stated that the movement of water in plants is due to both transpiration and root pressure.

In the dogwood under scrutiny and the maple being "milked," the same root pressure is at work.

Root pressure is caused by this accumulation of water in the xylem pushing on the rigid cells.

Such bleeding is similar to root pressure only sugars, rather than ions, may lower the xylem water potential.

Xylem sap will exude from the cut stem for hours or days due to root pressure.

The endodermis in the root is important in the development of root pressure.

Maples use root pressure each spring to force sap upwards from the roots, squeezing out any air bubbles.

The root pressure forces some water to exude through special leaf tip or edge structures, hydathodes, forming drops.

Physical arguments, in particular transpirational pull and root pressure, have since been shown to be adequate for explaining the ascent of sap.

The maximum root pressure measured in some plants can raise water only to about 7 meters, and the tallest trees are over 100 meters tall.

In one well-known study of root pressure, it was learned that sap of an American elm tree can rise 141 feet in an hour's time.

Root pressure is caused by active distribution of mineral nutrient ions into the root xylem.

Living root cells passively absorb water in the absence of transpiration pull via osmosis creating root pressure.