When it comes to growing crops, it is easy to look around at all of the living creatures in and around your growing space with suspicion and worry. While it's true, there are many organisms that become pests on farms and in the garden, there are multitudes of other beings that naturally occur in our bioregions that bring many benefits and can even be allies in our efforts to produce food. When growing crops organically, it's important to know who is a friend, who is a foe, who is a friend disguised as a foe and how to achieve a good ecological balance of all parties involved to help ensure a productive growing season.
Below we've highlighted some beneficial organisms that help us to produce healthy crops. In this blog we feature essential pollinators, predators of our worst pests, bioindicators of environmental conditions, and soil builders.
Somewhere between 75% and 95% of all flowering plants on the earth need to be pollinated. Pollinators provide pollination services to over 180,000 different plant species and more than 1,200 crops. Pollinating organisms which include bees, flies, mammals, birds, butterflies and beetles travel from plant to plant carrying pollen on their bodies. This process allows the transfer of genetic material critical to the reproductive system of flowering plants.
have specially developed, long, slender bills and tube-like tongues. They use their specialized beaks to drink nectar from brightly-colored flowers. Along with their pollinator services, they also feed on insects. Hummingbirds drink up to two times their body weight in nectar per day and as they move from plant to plant, they pollinate crops.
are the poster children for pollination due to their unmatched beauty, but surprisingly provide less pollinating services than bees and flies due to their thin legs and specialized mouth piece. Even so, as pollinators continue to decline
, all beneficial organisms that carry out this essential process are important. They are most active during the day and are highly susceptible to the use of pesticides. Some butterflies that pollinate crops and flowers in North America include:
Monarch, Eastern Swallowtail, Common Buckeye, Gulf Fritillary, Painted Lady, Spicebush Swallowtail, Zebra Longwing Butterfly, Frosted Elfin, Falcate Orangetip, Phaon Crescent, Skippers, Heliconius, Red Admiral
are avid pollinators that visit plants in the afternoon and overnight. They are often attracted to dull colored flowers and are drawn to plants with heavy fragrance. Some pollinating moth species include:
Hummingbird Hawk-Moth, Hummingbird Clearwing, White-lined Sphynx, Xanthopan, Hemaris, Snowberry Clearwing
Who knew a Housefly could actually contribute something good to this world? While flies
are often guilty of bringing the ick-factor to your picnic, they find their purpose among your crops. Many flies are essential pollinators and some of these include:
Syrphid Flies, Hoverflies, Biting Midges, Houseflies, Blowflies, Lovebugs, March Flies
Bees and Wasps
While the European honey bee is the most well known pollinating bee due to it's agricultural significance, there are over 4,000 other species of native bees and wasps
, including a vast array of solitary ground nesting species and many regional variations of Bumblebees, that contribute some level of pollination services to crops. Some of these bees and wasps include:
Solitary Bees, Honey Bees, Sweat Bees, Bumblebees, Pollen Wasps, Carpenter Bees, Fig Wasps, Paper Wasps, Yellow Jackets, Hair Wasps, Sphecidae Wasps
get a bad rap in our growing spaces as many of our worst pests arrive in beetle form. Not all beetles are bad, however, and some even provide essential pollinator services. Some pollinating beetles include:
False Blister Beetles, Soldier Beetles, Checkered Beetles, Soft-Wing Flower Beetles, Common Red Soldier Beetle
It's a bug-eat-bug world out there and it's good to know that where there are pests, there are also skilled hunters on your side. Cultural practices like frost cloth and timed plantings can help the organic grower avoid some of the worst of the season's pest pressure, but it's also good to remember that where nature throws out biodiversity, it is aiming for balance. Providing wild and native habitats surrounding growing spaces is a good first step for attracting beneficial predators.
While most small and large mammals that visit your growing space will be bringing with them crop loss, bats
are excellent nighttime hunters and pollinators that can be great allies in the garden. They won't make a nest in your hair, but they will catch pollen on the hairs of their bodies and carry it to the next flower and feed on insect pests including:
Army Worms, June Beetles, Cucumber Beetles, Grasshoppers, Corn Earworms, Mosquitoes, Stink Bugs
of all kinds are great allies for the healthy development of crops. Supporting a diversity of bird life is not only a beautiful sight to behold, it can help with the management of a wide array of pests. There are birds that specialize in eating insects, small mammals and will even help reduce weeds by feeding on weed seeds. Some helpful North American bird allies include:
Eastern Bluebirds, Cardinals, Grosbeaks, Hawks, Nuthatches, Orioles, Owls, Sparrows, Swallows, Titmice, Warblers, Woodpeckers, Purple Martins, Wrens, Chickadees, Tanagers, Goldfinches
Reptiles and Amphibians
While your amphibian, turtle and lizard
friends handle your insect pests, snakes
will eat insects but also troublesome mammal pests like chipmunks, gophers, mice, moles and even rabbits. Your reptile and amphibian crop protectors include:
Snakes, Frogs, Lizards, Toads, Salamanders, Newts, Turtles, Skinks
The tiny wars that take place on your plants everyday may go unnoticed as you try to keep up with the needs of your plants, but you can rest assured that where there are pests eating your crops, there are predator insects
eating those pests. Some of the most helpful predators that focus on the pests inhabiting plant leaves and soils include:
Ladybugs, Braconid Wasps, Lacewings, Praying Mantis, Pirate Bugs, Damsel Bugs, Ground Beetles, Big Eyed Bug, Soldier Beetles, Tachinid Flies, Spiders, Rove Beetles, Hornets
The simple definition of a bioindicator is an organism whose status in an ecosystem is analyzed as an indication of the ecosystem's heath. Ecologists select specific organisms as markers for ecological health based off of a few guiding principles. They are generally readily occurring organisms that are not considered rare but do require clean water and soil, ample biological diversity and a well developed nutrient cycle to thrive. When we find these species in our cultivated spaces, it is a good indicator that we are creating a healthy habitat that is capable of sustaining complex ecology and thus, is likely to produce healthy crops.
are excellent bioindicators of environmental pollution due to their susceptibility to toxins and chemicals during their freshwater cycles. Amphibians spend time on land and time in local waterways and respire through their mouths, lungs and skin. This makes them extremely vulnerable to chemical buildup. When you see things like frogs, salamanders and toads in your growing spaces, you can rest assured that you're waterways and soils are likely free of built up toxins and chemical residues.
may be a nuisance in the garden and on the farm, but the plants that voluntarily germinate and flourish in our cultivated spaces can tell us a lot about the conditions of the soil. Plants are as different as people and each individual species needs different conditions to thrive. Using weeds as indicators for soil quality can look a little like this:
- Mullein, Sheep's Sorrel, Shepherd's Purse, Crabgrass, Lespedeza, Carpetgrass, Broomsedge, Horsetail, Daisy, Dandelions, Ragweed, Wild Carrot, Vetch
- Lambsquarters, Common Groundsel, Chickweed, Chicory, Purple Deadnettle, Purslane, Mugwort, Stinging Nettle, Clover, Galinsoga, Wood Sorrel,
- Plantain, Thistles, Knotweed, Quack Grass, Dallis Grass, Pigweed, Bindweed, Dock
- Yarrow, Wild Mustard, Speedwell, Cat's Ear, Mullein, Yellow Hawk Weed, Sheep Sorrel, Carpetweed
Poor Draining Soils
- Moss, Dock, Dollarweed, Buttercups, Purple and Yellow Nutsedge, Bermuda Grass, Ground Ivy, Horsenettle, Hairy Bittercress, Joe-Pye Weed, Horsetail
When a soil ecosystem is healthy and effectively cycling nutrients, it is incredible how much diversity can be found from the subsoil to the leaves of your plants. Often times, a soil that is highly active will be inundated with creepy little creatures
that might look like nightmares but are a dream come true for healthy crops. Some indicators of healthy soils include:
Soil Isopods, Earthworms, Snails, Millipedes, Gnaphosidae Spiders, Arctiidae Moths, Chrysomelidae Leaf Beetles
(These specific examples are effective bioindicators due to their susceptibility to degradation of ecological integrity. When conditions worsen or rapidly change, these organisms will become scarce or even disappear.)
From the microscopic to the visible, there is an almost infinite collection of organisms that help build soil
. Often times, plants through their sugar exudation process as a result of photosynthesis, will attract the very organisms they need to thrive. Some micro and macro organisms and fungi that provide essential soil building services to plants include:
Grubs, Earthworms, Springtails, Ants, Mites, Dung Beetles, Termites, Fungi, Bacteria, Algae, Archaea, Protozoa, Nematodes