Posted: April 11, 2013, 3:00 p.m. PDT
How much do you know about the two most-popular seeds to lure birds to feeders? We often learn everything possible about the birds that come into view, but you also might like to know the history of Nyjer, formerly known as thistle, and black-oil sunflower seed. While learning about seed may not seem quite as exciting as studying birds, it’s bound to add to your enjoyment.
My father affectionately referred to this little seed as "black gold," because he could never quite accept the price that he had to pay for this finch and siskin magnet. It is an expensive seed, but once you see a feeder festooned with goldfinches, you’ll gladly pay the price.
Nyjer bird seed used to be known as thistle seed.
This seed is undergoing a name change every bit as newsworthy as that undertaken by the artist formerly known as Prince. As a youngster, I (OK, my dad) bought the seed as thistle. Today, it is increasingly known as Nyjer, a 1998 registered trademark of the Wild Bird Feeding Industry.
The institute promoted the change because the seed does not come from the thistle plant, several species of which are considered noxious and a threat to biological diversity in North America. WBFI promotes the use of the word "Nyjer" to reduce the potential for the offensive mispronunciation of the word "niger," the official common name for this seed.
How the seed came to be known as thistle is unclear. Online retailer Shaw Creek Bird Supply Company suggests that it might be due to the fact that goldfinches and other birds that eat Nyjer eat the seeds of the real thistle and use the downy fluff from these plants to line their nests. The finch’s association with thistle might have been enough for some distributors to start promoting the seed by this name.
Conservationists, however, do not hold many species of non-native thistles in high esteem. The "bad" thistles — which originate in Europe, Africa and Asia — include several species that pose a serious risk to our native flora and fauna.
For example, the California Native Plant Society notes that the yellow star thistle (Centaurea solstitialis) has invaded more than one-tenth of the state, including 10 million acres of rangelands. The plant is toxic to horses, displaces native plants and increases fire hazards. With this kind of reputation, it’s no wonder that WBFI wanted to set the story straight.
The little black seed that we load into our feeders is harvested from Guizotia abyssinica, a member of the Asteracae family. This yellow-flowering plant (thistles are pink to purple) is cultivated in Ethiopia, India, Myanmar and Nepal but imported to the United States from the first two countries.
According to WBFI, it is the only major wild bird feed ingredient imported into North America from overseas. The U.S Department of Agriculture controls the importation and requires that the seeds be heat-treated at a temperature of 250 degrees Fahrenheit. The exposure to that temperature for 15 minutes destroys any weed seeds and prevents them from germinating — a key way to prevent the accidental introduction of potentially dangerous, invasive, exotic plants, such as thistle.
Nyjer’s valuable oil is used in foods, paints and soaps and as an illuminant. Purdue University’s department of horticulture and landscape notes that the oil can substitute for olive oil and can be mixed with linseed oil.
The seeds themselves can be consumed fried or as a condiment. In Ethiopia, the seeds are mixed with honey and pressed into cakes for use as livestock feed. The plant itself is used as green manure in the pre-flowering stage.
The genus Guizotia includes six species, of which niger and four others are native to the highlands of Ethiopia. The Guizotia abyssinica plant grows to a height of about 41/2 feet. The yellow flowers might be arranged singularly or in small clusters up to 5 inches across.
In tropical areas, farmers sow Nyjer seeds in rows about 10 inches apart or mix it with fertilizer, scatter the mixture and worked it into the soil with a light harrowing. The seeds germinate in about two days and are thinned after about a week. Twelve to 18 weeks after planting, farmers harvest the crop. Traditionally, they harvest it while the buds are still yellow, then stack it to dry and transport it upright to the threshing ground. Threshing is relatively easy, because the seeds are loosely held in the flower heads.
The seed’s small size and its 40 percent oil content drive our finches crazy. The Purdue website reveals that each 100 grams of the seed contains 31 to 34 grams of fat, along with lots of carbohydrate and protein.
Karen Jones-Burns, vice president of operations for ETO Sterilization, the company that performs the heat treatment on the seed, estimates that about 50,000 metric tons of Nyjer enter the United States each year. Good news for siskins and goldfinches!
I consider pouring a 20-pound bag of black-oil sunflower into the metal storage container in my garage one of my greatest pleasures. The texture, smell and sight of the glossy black shells delight my senses.
Although I always think "tube feeder" when I see sunflower, bird food represents only a small portion of the market for this valuable seed. About 70 percent of the crop’s value comes from the valuable oil, prized for its nearly clear color, unsaturated fatty acids and other desirable factors for cooking and food production. The University of Wisconsin’s Alternative Crops Manual notes that in the mid-1980s, sunflower seed was the third-largest source of vegetable oil in the world, behind soybean and palm.
Many Europeans prefer sunflower oil for cooking, and more North Americans have responded to the introduction of oleic types of sunflower, which are better for frying uses and also extend the shelf life of snacks. Europe and Russia produce the most sunflower seeds.
As any regular visitor to the snack aisle in the local supermarket can tell you, humans really like sunflowers. Typically the largest seeds — often the striped variety — are roasted in their shells, with the next-largest seeds stripped of their hulls and sold as nutritional treats.
The smallest seeds are reserved for the bird food market. That’s OK, though, because the smaller seeds, usually the black-oil variety, are rich in the high-
energy oils and easier for many smaller seed-eating birds, such as chickadees and nuthatches, to handle.
Not surprisingly, the sunflower’s rich oil content makes it popular with birds. The Alternative Crops Manual describes sunflower as having 39 percent to 49 percent oil in the seed, so it’s a source of high energy for birds and people.
The sunflower (Helianthus annuus) is one of 67 members of the genus Helianthus, all native to the Americas. Botanists recognize it as a member of the composite family. The striking head of the sunflower is not a single flower but 1,000 to 2,000 smaller flowers, each of which might turn into a seed.
Although the history of its first cultivation is unclear, North American Indians apparently used sunflowers before European colonization of the New World. Anderson Seed Company describes sunflower as a common crop among Indian tribes across the continent, with evidence that the plant was cultivated in the Southwest as early as 3000 B.C.
Sunflower might have been cultivated before corn. Indians ground or pounded the seed into flour for bread, cakes and mush. As meal, it might have been mixed with other vegetables such as beans and squash. It also had uses as a medicinal crop (snakebite treatment, among others), a source of dyes, and oil for ceremonial body painting and pottery.
The sunflower (Helianthus annuus) is one of 67 members of the genus Helianthus.
Early French, Spanish and English explorers took the seeds to their native lands, probably by 1500 or so, according to Anderson Seed Company. From there, its use spread along the trade routes to Italy, Egypt, Afghanistan, India, China and Russia. By the early 1700s, the English were squeezing oil from the seeds, and by the early 1800s, oil was produced on a commercial scale.
The Russian Orthodox Church apparently played a big role in the oil’s popularity. The church forbade most oil foods during Lent, but sunflower was not on the list and quickly gained a following.
By the early 19th century, Russia cultivated more than 2 million acres. It was about this time that two real seed types were recognized: the larger seed that was eaten as a food and the smaller variety that was rich in oil.
After this long tour of the Old World, the sunflower returned to North America for commercial uses in the late 1800s. Although the plant’s first use appears to have been silage for poultry, the Missouri Sunflower Grower’s Association was processing the seed into oil by 1926.
Industry experts estimate that about 500,000 acres in the United States and Canada grow sunflower for birdfeeding purposes. Close to 800 million pounds or so makes its way into our backyard feeders.
Ironically, sunflower farmers consider birds a major pest in some areas, particularly the Great Plains. Flocks of blackbirds, particularly Red-winged and Yellow-headed, and Common Grackles might descend on fields of ripening seeds and cause considerable economic impacts. Losses to farmers in this area are estimated to be $4 million to $7 million annually.
Recent plans to poison blackbird flocks created considerable controversy and stimulated research on alternative approaches. These include managing the preferred cattail marsh roosting sites near sunflower fields, creating "decoy" crops to lure the birds from commercial sunflower fields, and identifying repellents. Birders likely can contribute to that research.
Birdfeeding is an adventure in many ways. Now that you know a little more about the origin of the seeds that we share with the birds, you have one more good excuse to hang a new feeder.
Excerpt from WildBird, November/December 2005 issue, with permission from its publisher, I-5 Publishing LLC. To purchase digital back issues of WildBird Magazine, click here.