What is the most massive living organism on planet earth? The answer is actually not a blue whale. Or the great barrier reef.

The Humongous Fungus in Malheur National Forest in Oregon takes the record for the largest organism by an expanse of acreage, but there is still one more organism that is even larger by mass.

The answer is the Pando Aspen Grove located on the Colorado Plateau in Southern Utah. The Pando Aspen Grove is the world’s most massive living organism and is estimated to be around 80,000 years old.

Aspen Groves as One Huge Organism joined at the Roots

Aspens are a fascinating tree. Aspen trees do not stand alone with their own root and a vascular system like most other plants do. Aspen groves are one enormous organism connected by a single root system. Aspens do not grow from seeds. They grow by sprouting new trees from their roots. These are called root suckers. Each aspen in a shared root system is genetically identical.



It is easy to spot which aspens are connected when the leaves change color in the fall. Each of the trees in a connected grove will all start to change the color of their leaves from green to yellow simultaneously.

The Lifespan of an Aspen Tree

Aspen trees can grow in elevations from 6500 to 11,500 feet, but they do best naturally at altitudes above 8000 feet. Aspen trees are more vulnerable to warm drought. They can thrive for a while at a lower elevation, but they typically do not live as long in the warmer climates as they do in the cooler mountain temperatures.

At a higher elevation, the individual trees often live to be around 150 years old, however, the grove as a whole can live to be thousands of years old as the root suckers are replenished. In the city of Colorado Springs, the lifespan of an individual aspen tree averages closer to 20 to 40 years due to the warmer climate, but small groves can live much longer.

Growing Aspen Trees in the City

Aspen trees can be grown from transplanted root suckers. This typically involves taking a root sucker from the parent tree once it has grown to be at least 12 to 20 inches tall. The root sucker should be taken out with at least 15 inches of the root system to ensure healthy growth.

Once the root sucker is removed it should be planted in a sunny area with deep, moist soil.

Full-grown aspen trees will continue to propagate through root suckers. When there is at least one aspen tree in a yard, there will soon be little shoots of baby aspen root suckers. Many homeowners opt to remove the root suckers as they come up, but allowing the aspens to grow into a small grove will help the trees to grow to be stronger.

Remember, aspens are a collective species, so the stronger the grove and root system, the stronger the individual tree.

Aspen Tree Care

Aspen trees have very large root systems, so having room to spread out is especially important. Aspen trees can grow in a variety of soils, but they do best in more acidic soils with good drainage.

Aspen trees benefit greatly from regular watering. Aspen trees are used to cool climates, so they can be more affected by summer droughts than other trees, but regular watering can help with this greatly.

Oystershell scale is a tree pest that impacts aspen trees. These can be removed from the aspen trees by spraying with high-pressure water. It is fine to hose down the tree at any time. Chemical applications may also be beneficial when the Oystershell scale is in the crawler stage. If an aspen tree seems to be affected by pests, contact your local tree service professional to determine how best to mitigate it.

Aspen Tree Pruning Colorado Springs

Pruning aspen trees primarily involves thinning out the root sucker shoots.

Individual aspen trees tend to naturally grow very nicely individually, but their shoots can become a little overgrown, and sometimes even weedy. Since this is the aspen’s way of establishing longevity, it is good to keep some of these shoots to promote a healthy grove, but often some will need to be removed to keep a yard looking nice. Root suckers can be cut back at their base to be removed. This will need to be done regularly as the aspen grove continues to grow.

Contact your local tree service company for any questions regarding your aspen trees. Precision Tree has been in business for 19 years and is ready to answer your tree questions.

From Evergreen Trees to Aspen Trees, we  are your tree care specialists!