What does roots do

Estimated read time:. Imagine walking out into a crop field or pasture. What do you notice? Perhaps you see amber waves of grain out to the horizon or hear the leaves rustling in a cool breeze. What lurks in that hidden world, and why does it matter to you? As you look at all the growth aboveground, you might consider that just as much plant mass is invested in roots.

In fact, in the springtime, 1 acre of grassland or pasture may have about 1, pounds of standing shoot mass aboveground but as much as 3, pounds of roots below ground, in the top foot of soil. Download Infographic. Plants are like a factory, using energy from sunlight to produce sugar in their leaves that provides the carbon backbones for making all the other molecules required for life. It can plumb very deep water sources and store a lot of food to help the plant survive drought and other environmental extremes.

The taproot also anchors the plant very securely in the ground. Fibrous root systems have many small branching roots, called fibrous roots , but no large primary root. The huge number of threadlike roots increases the surface area for absorption of water and minerals, but fibrous roots anchor the plant less securely.

Dandelions have taproot systems; grasses have fibrous root systems. Root Structures and Functions As shown in Figure below , the tip of a root is called the root cap.

Absorbing water and minerals: Thin-walled epidermal cells and root hairs are well suited to absorb water and dissolved minerals from the soil. The roots of many plants also have a mycorrhizal relationship with fungi for greater absorption. Anchoring and supporting the plant: Root systems help anchor plants to the ground, allowing plants to grow tall without toppling over.

A tough covering may replace the epidermis in older roots, making them ropelike and even stronger. As shown in Figure below , some roots have unusual specializations for anchoring plants.

Storing food: In many plants, ground tissues in roots store food produced by the leaves during photosynthesis. The bloodroot shown in Figure below stores food in its roots over the winter. Root Growth Roots have primary and secondary meristems for growth in length and width. Summary Roots absorb water and minerals and transport them to stems. They also anchor and support a plant, and store food.

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Soil Res. Limp or yellow leaves can indicate that a plant has been exposed to stressful conditions. But just like people and pets, plants can recover from stress to lead long and production lives.

How to know if your plant will recover? Take a look at those roots. Healthy roots make a healthy plant. And healthy plants recover from stress. Some plants actually develop particularly brittle leaves and stems to allow the plant to easily sacrifice top growth to herbivores or stress while protecting their all-important root structure.

Both grass and dandelions easily tolerate munching herbivores or lawn mower blades, rapidly producing fresh foliage to replace what is lost, while their root structure is extremely resistant to harm, thereby ensuring a long life for both the lawn and the weed. Alstroemeria are a great garden example similar to these plants. Alstroemeria produce lush foliage and loads of flowers for months at a time. These flower factories are powered by extraordinary root structures that enable them to be highly adaptable in the home garden.

The stress of too much or too little water, high heat, foot traffic, fire or even being shipped can cause the top growth of alstroemeria to yellow and go limp. Far from damaging the health of the plant, this is a strategy the plant has developed to survive stressful conditions.

This allows the plant to conserve its energies to quickly replenish the damaged top growth with a flush of new leaves and blooms once the stressful conditions have passed.

Here, we can see the exceptional root structure of an alstroemeria plug. The super thick roots are storing energy for the plant's future needs, while the finer roots take up water and nutrients to feed the plant's current top growth. If your alstroemeria plant looks like this, with dark green leaves and a robust root ball, loosen the roots to help them to spread out in the new location, then transplant it to a new pot or the ground with loose, nutritious soil.