About Mycorrhizal Online

A family-owned wholesale distributor connecting professional growers with the science of healthy roots - based in Grants Pass, Oregon.

Pioneers of the Mycorrhizal Industry

Dr. Mike Amaranthus holding a large mushroom

Dr. Mike Amaranthus with a giant mushroom

In 1985, Mike Amaranthus was working for the U.S. Forest Service on reforestation projects in Southern Oregon, where vast areas of wilderness had been devastated by wildfire. Like many foresters at the time, he relied on traditional fertilizers to help newly planted pine seedlings survive in dry conditions and nutrient-poor soils. However, the results were disappointing, and many reforestation efforts continued to struggle.

Determined to find a better solution, Mike sought advice from a colleague after witnessing one project after another fail. That recommendation led him to Oregon State University and renowned mycologist Dr. Jim Trappe. Dr. Trappe suggested that Mike focus on a specific type of mushroom that naturally forms a symbiotic relationship with the native pine species he was planting.

That fall, Mike set out to find Rhizopogon truffles in the forest. Using squirrel diggings as clues and a potato hoe as his tool, he collected the truffles and brought them home. There, he ground them into a powder, mixed them with water using his kitchen blender, and created a simple mycorrhizal inoculant.

The following planting season, Mike applied the mycorrhizae to pine seedlings and was amazed by the results. The trees showed dramatically improved survival and growth compared to those treated with conventional fertilizers alone. This breakthrough convinced him that mycorrhizal fungi could play a critical role in successful reforestation.

Dr. Mike Amaranthus in the lab

Inspired by these findings, Mike enrolled at Oregon State University to study mycorrhizae. After earning his doctorate, Dr. Mike Amaranthus became one of the world's leading experts in mycorrhizal fungi by authoring over 100 scientific papers and earning the Department of Agriculture's highest honors for scientific achievement. His research and innovations helped revolutionize the understanding and application of mycorrhizae in forestry, agriculture, and ecosystem restoration. Throughout his career, he received numerous other awards and was featured on the television series Modern Marvels for his groundbreaking work.

By the mid-2010s, products developed by Dr. Amaranthus and his Southern Oregon-based company were being used in over 30 countries worldwide, making his operation one of the most effective and influential sources of commercial mycorrhizal inoculants. What began with a search for a better way to restore burned forests ultimately helped transform an entire industry and advanced the global understanding of the vital relationship between plants and fungi.

Mike and Zack Amaranthus

In 2016, Zack Amaranthus, Mike's son, entered the mycorrhizal industry and founded his own company. Drawing on decades of family expertise, and adding new technological advancements, Zack began distributing MycoApply®, the family's original mycorrhizal brand, while also developing the innovative Big Foot® product line. Through these efforts, he continues the Amaranthus family's long-standing commitment to advancing mycorrhizal technology and helping growers produce healthier, more vigorous, and more productive plants.

Mike Amaranthus holding tree seedlings Zack Amaranthus as a young gardener Zack Amaranthus holding plants

Authorized Distributor

We are fully authorized by both Mycorrhizal Applications and Big Foot Mycorrhizae. Every product ships genuine, guaranteed.

True Wholesale Pricing

No retail markup. We sell full-size bags and cases at direct distributor pricing to nurseries, farms, and landscapers.

Same-Day Fulfillment

Orders placed on business days ship promptly with full tracking - so your operation never waits on product.