July, 2006 Issues of Woodland Walkers Guide These are stories of the walks our collie has enticed us into taking as published in "The Home News", Spring Green's local paper. .

July 24, 2006

This is the second and last year I will grow a particular species of nicotiana in my garden, as both times the plants have proved extremely attractive to aphids. The upper leaves and buds are covered with the tiny creatures, and although the plants continue to grow, their beauty is greatly diminished. Everyone knows that aphids, or plant-lice as they are often called, are pesky nuisances that suck the life out of one's garden plants; still, the truth is that they are fascinating animals that have evolved some unique life strategies. Read on and I hope that by the time you have finished you will at least examine them carefully before you obliterate them.

The aphid is a small soft-bodied insect, most commonly wingless, with a tiny head and large fat body. Its mouthparts include very thin delicate tubes called stylets that it inserts into a leaf or soft stem to reach the sap inside. Sap is a solution rich in sugars manufactured by the plant through photosynthesis, and carried by way of phloem tubes to the roots or into storage structures, such as tubers or bulbs. Some aphids feed by inserting their stylets through the pores of the plant leaves but most must push them in between or through the cell walls. The delicate points could be damaged during penetration, but the aphid secretes a special liquid from the tips that immediately hardens to form a protective sheath around them. It then slowly inserts them into the plant in search of the phloem tubes and when it finds one the aphid injects saliva into the plant cell. The purpose of this is unknown but it is suspected that this saliva helps prevent the plant cell from sealing the puncture. It can require anywhere from 25 minutes to 24 hours to insert the stylets and actually begin feeding.

Plant saps may be rich in sugars but they are poor in amino acids, and aphids must drink far more sap than they need in order to get enough of these substances in their diet. As a result, they excrete large amounts of excess sugary liquid, often called honeydew, and this can often be seen on the lower leaves of infested plants. A number of other insects find this honeydew attractive; in fact, some species of ants develop very close relationships with certain aphids to obtain the honeydew that the aphids secrete. A common meadow ant even collects the eggs of a root-aphid in the autumn and stores them in its nest. Then, in spring the eggs are moved to special chambers adjacent to plant roots so that the aphid nymphs can feed as soon as they hatch. Other species of ants tend a variety of feeding aphids, protecting them from various predators and moving them to new plants if their hosts lose vigor. Since many adult ants seem to require only sugars in their diet, honeydew is a perfect food for them.

Most of the time aphids do not have wings, and unless they are attacked or their plant dies, they do little but feed and give birth. However, environmental changes or overpopulation will result in some hatchlings possessing wings that allow them to fly to more favorable sites. Aphids are weak fliers but they often take advantage of favorable winds to carry them to new areas.

Aphids survive the winter through their eggs produced in the autumn by fertilized females. Interestingly, all the spring hatchlings are female, and although most will be wingless, under certain conditions some may have wings. Eggs start to develop inside the insect immediately after ovulation, and since this occurs long before it gives birth, this means that an embryo can exist inside another larger and more mature embryo. In fact, a newly born aphid can contain not only the developing embryos of her daughters but also those of her granddaughters which are developing within her daughters. Under favorable environmental conditions, a newly born aphid becomes a reproducing adult within 7 days, and can produce up to 5 offspring per day for up to 30 days. It is common for aphid populations to double every two days, and someone calculated that some species could produce up to 41 generations of offspring in an average summer. It is almost unbelievable, but if none died, there would be more than one and a half billion billion billion aphids by the end of the season.

It is fascinating to question how young born from many asexual generations can at times produce both fertile male and female offspring, as well as winged and wingless forms. Although scientists are unsure of the complete answer, it is felt that the falling temperatures of autumn and the growing scarcity of food are important stimuli. The winged males and females mate and the females lay the fertilized eggs that are destined to carry the species through the cold months of winter. Incidentally, if the aphids live in tropical areas or are protected in a heated building, they may go on reproducing asexually indefinitely. Even though only about seven percent of the 4000 species of aphids in the world are serious pests, their very large populations can cause severe damage to crops and important economic losses. It is one of our ongoing fights.

July 17, 2006

"He loves me; he loves me not." There's hardly a girl (nor a boy either), who has not queried a daisy, plucking off petal after petal, and always making sure the answer is the desired one. This game originated during Victorian times and is only part of the folklore associated with this flower. "Daisy" is such a well used name that most everyone assumes it is a common native wildflower in this country, and indeed, there are so many in some places that one species has been designated "invasive" and outlawed. There is no native daisy in America, however, and the ancestors of all those decorating our roadsides and fields were introduced at some time or another.

Although many people call any open-faced flower such as fleabane or aster by the title "daisy", the name actually refers to one of the dozen or so European species. Most widely known there is simply called the common daisy, and it is native to western, central and northern Europe. It is a small plant with white flowers little more than an inch across, rounded evergreen leaves and short creeping rhizomes. Because it is not affected by mowing, it is often considered to be a weed in lawns by some, though many appreciate the flowers. Perhaps you are familiar with one of the several cultivars and hybrids that have been developed from this plant. They have much larger pink to purple flower heads, and are sold under the name English daisy.

Much more commonly seen in this country but also an import from Europe, is the oxeye daisy (not to be confused with the oxeye, a native sunflower). It grows up to two feet in height and has the classic appearance, with a single circle of fifteen to twenty white petals around a yellow center. This plant is actually in the chrysanthemum family and is one of our toughest and most persistent escapees. Often the earliest wild perennial to bloom in the spring fields, it forms expanding clumps each successive year, all the while seeding new ones. Prolific and aggressive, it has become such a problem that a dozen states (Wisconsin is so far not among them) have declared it a menace and destroy it on sight.

Spain and Portugal were home to a larger daisy-like chrysanthemum species, the Shasta daisy, which can grow up to 3 ft. tall. This, too, has been extensively altered by horticulturists and is now an important species in many perennial gardens around the world. Its seed is frequently carried off into surrounding areas by birds and animals, reverting quickly to its original form, but it has never become the problem posed by the oxeye daisy.

At this time of year, a whole new set of introduced flowers gone wild decorate our roadsides and fallow fields. Queen Anne's lace, a close relative of our garden carrot, is an erect biennial, meaning it forms a rosette its first year, and then puts up a bloom stalk and then sets seeds before dying the next. Spotted knapweed is also much in evidence as it has spread into large colonies along Highway 14. Its small flowers are so numerous that they give the roadside a lavender cast. Two thistles are also showing pinkish-lavender flowers. The bull thistle is a coarse, branched biennial, generally between three to four feet tall. It has vicious spines that make it very uncomfortable to get close to but it does have lovely flowers that contain much nectar, and its seeds are relished by many birds, particularly the goldfinch. Canada thistle is much more of a problem, as it is an aggressive perennial weed that spreads from deep rhizomes to form dense and persistent colonies. The rather thin stems are two to four feet tall and branch at the top to produce numerous inch wide flowers.

If chicory could keep its lovely blue blossoms open throughout the day, I think it would be added to many a garden, but as it is, it stands barren and ugly after midday. It has a common name of "coffeeweed" because its roots can be dried, roasted and used as a substitute for coffee, and some Europeans have found that it makes a good hay crop. It is also grown for a substance that is used in bread and pastries to bring out the flavor of sugar. Hairy and crown vetch, red clover, and orange daylilies are also roadside residents. Sweetclover, very prominent this year, is tall and gangly, but very fragrant, and there are numerous clumps of bouncing bet, a phlox that has been around so long that my mother preserved a pressed stalk in her wildflower collection assembled for her teacher's certificate in rural Ohio in 1910.

While we worry about these introduced plants invading our wild places, they do quickly colonize waste areas and roadsides, as well, turning barren spots into gardens of sorts and adding color and interest. Since there is little we can do about them, I guess we might as well enjoy them.

July 10, 2006

The white fluff-ball crouched on the edge of our neighbors' drive, its big yellow eyes staring defiantly up at anyone who approached, its tiny beak clicking aggressively. It was barely three weeks old that day in early May, but already showed the defiance and fearlessness of the avian predator it would become, and even the farmyard cats seemed to feel that discretion was the better part of valor and watched from a distance. An adult owl scolded and postured from a branch of a nearby tree, but soon flew away, not to be seen again. Bennie and Char searched the thick tangle of branches in the grove of white pines that bordered the driveway, knowing there must be a nest, but could see no sign of it nor any spot to safely stash the chick. They finally consulted with Linda Bethke, a licensed bird rehabilitator from Prairie du Sac, and concluded that it would be best to collect the baby and give it over into her care. She instructed them to drop a towel over it to protect both their hands and the infant, place it in a box, and deliver it to her facility, the Soaring Eagle Wildlife Rehabilitation Center. There, Linda identified the chick as a long-eared owl, and settled it into its new foster home.

The adult long-eared owl is medium-sized, half way between a great horned and screech owl, and averages 14 inches long with a wingspan of about 39 inches. Its "ears", that are actually tufts of feathers, rise more nearly from the center of the head and it lacks the white throat of the great horned; also, the pattern of markings on its body run up and down instead of crosswise. When perched, the long-eared the owl stretches out its body and ear tufts and compresses its feathers, making itself into a believable tree limb. It is mostly silent except during the breeding season, but then uses a wide repertoire of calls. That of the male is often a low, slow "hoo, hoo, hoo, hoo, .....", repeated up to 100 times, while the female responds with a raspy buzz call. When alarmed, both sexes can bark, hiss or shriek like a cat.

Long-eared owls are birds of open woodlands and forest edges, as they require thickly wooded areas for nesting and roosting, and nearby open spaces for hunting. In late winter, the male hunts out one or more old stick nests of a crow or hawk, preferably screened by vines or branches and 20-30 feet above ground. He announces his find and performs elaborate flights over each nest, and if a female accepts his choice, they mate and refurbish the nest with a few feathers and leaves. She will lay from 3 to 8 eggs (usually 4 to 5) at 1 to 5 day intervals, and begins incubating them immediately so that the clutch hatches over an extended period. The older of the crowded nestlings begin to climb out of the nest onto nearby branches at about 21 days, even though they will not be able to fly for several more weeks. The parents continue to tend all of them until they are independent at about 3 months, and the family group keeps more or less together well into the winter.

Long-eared Owls hunt mainly by ranging over open pastures and fields from late dusk to just before dawn, flying only a few feet above the ground. They are very agile and can fly through fairly dense brush, often stopping to hover while searching. When prey is spotted, the owl pounces with its powerful talons and snatches up its victim, often swallowing it immediately or else carrying it off to the nest or favorite perch. Prey is most commonly voles and deer mice but they also eat squirrels, bats, chipmunks, shrews, and small cottontails, as well as birds, insects, frogs, and snakes. Two-inch pellets are regurgitated several hours after eating, containing undigested hair, bones, and teeth.

Some long-eared owls migrate considerable distances (such as one banded Minnesota bird that was found in Mexico), but if sufficient prey is available, many seem to spend their winters where they breed if there are dense conifer groves or brushy thickets in which to roost. Adult long-eared owls are preyed upon by many other raptors including great-horned owls, barred owls and red-tailed hawks, and nestlings are vulnerable to bull snakes, crows, and raccoons, as well. Vehicles and guns also provide a constant threat.

Our local chick has grown amazingly under Linda's care, and when it has learned to hunt it will be released in the area. She has several other owl babies to tutor, as well, but her 17 years experience with more than 120 species has made her quite capable of giving them the help they need. Linda is one of three dedicated women who make up the Soaring Eagle Wildlife Rehabilitation Center, Inc.; others are Joolene Hoskins-Severson of Baraboo who works with raptors, and Sue Walkowiak of Montello, who cares for baby songbirds and waterfowl. Also vital to their efforts are the skills of veterinarian Joseph Kelley of the Sauk Prairie Small Animal Clinic, who donates his time and expertise. She tells me they are currently hoping to build a flight building on a plot to the east of Prairie du Sac, where young birds can learn the skills they need to survive.

Last year Wisconsin lost about half of its rehabilitators due to new DNR requirements for additional testing and facility inspections, and Linda reports that those that remain are greatly overstretched. Soaring Eagle, that currently serves a seven county area, badly needs two additional rehabilitators for mammals and baby songbirds. This work is expensive in time, energy and money and Linda receives no government help for her costs, dipping into family funds for all expenses. I know that any contributions toward her work would be greatly appreciated and we wildlife-enthusiasts could feel that we are helping in a much-needed enterprise. Contact her at 608-643-8390 or at 105 Prairie Ave., Prairie du Sac.

There is a relatively new grass that is popping up throughout our area that bothers me and other prairie enthusiasts. Called reed canary grass, it is a coarse, sod-forming perennial, native to regions of Europe and Asia. It can grow up to 6 feet tall, and spreads quickly into large sods, overwhelming anything it touches. Although its greatest threat is to marshes and other wetlands, it seems to be able to survive and even thrive on our hilltop prairie as well. It is easiest to identify when the tan seed heads form, as these are compact and 3-6" long, and stand well above the coarse leaves. The leaves are also somewhat distinctive as they grow out at regular intervals from the jointed stems and may be up to _" wide. We have half a dozen colonies growing on our farm, and despite my early attempts to eradicate them, more appear every year.

There is a similar but less-invasive variation of this species native to this country, but the import is spreading rapidly across the northern half of America. Even more frustrating is the fact that it was introduced intentionally, as it was thought to be an excellent forage crop and a solution to erosion. Too late, it was discovered to be almost impossible to control as it spreads not only by seed but also by means of stout, aggressive creeping rhizomes. It is usually not feasible to use any of the commonly employed control measures such as cultivation and chemicals, as the rhizomes are very difficult to kill and herbicides affect surrounding desirable plants as well. The one exception is fire, as repeated late autumn or late spring burning has been found to be somewhat effective, and does not injure most native species.

Of course, reed canary is not the only invasive grass on our prairies and in our fields. Quack grass, like many of our weeds, was introduced from Europe and is a common sight in our gardens and across the country where it crowds out valuable crops. It is rather coarse, 1 to 3 feet high, and when in flower resembles rye or beardless wheat. Its smooth hollow stems are thickened at the joints and produced from a long, creeping rootstock. The tips of these growing roots are sharp enough to prick one's finger and I have seen them pierce plastic sheeting as well as other objects in their path as they push through the soil.

Also troublesome is crab grass. It typically has spreading stems with wide flat leaf blades that lay on the ground with the tips bending up. It is hated because its coarseness stands out in a tended lawn, and is such a rapid grower that a stand can quickly out-compete desirable species. It is an annual plant and so is killed by heavy frost, but one specimen is capable of producing 150,000 seeds in a season and they spread everywhere.

It has been estimated that the grasses comprise 20% of the vegetation of the earth, and they are far more important to our lives than we might realize. For one thing, the grass group is a major human food source all over the world, and includes rice, corn, wheat, oats, as well as other grains; in addition, some have been cultivated as food for domesticated animals for up to 10,000 years. In some parts of the world, people use grasses such as bamboo in construction, and wherever it grows, grass plays a vital role in curbing erosion. Various species are used to make sugar, liquor, bread and plastics, and even reeds for certain musical instruments. Grass has been used to make paper since at least as early as 2400 B.C.

Grasses have a very simple structure, and a very simple way of life. At the base of the plant, roots grow down into the earth, collecting nutrients, soaking up water and securing the plant to the ground. Hollow rigid stems grow up from a crown and are jointed at nodes, from which protrude narrow leaves. Like the leaves on a tree, grass leaves collect energy from sunlight through photosynthesis and obtain their green color from chlorophyll. They have small, wind-pollinated flowers that lack petals and are grouped into spikelets that eventually develop into dry seed-like fruit.

A large portion of the pre-settlement country was prairie with three species predominate: big bluestem, Indian grass, and, in wetter areas, prairie cord grass. These could stand 9 feet tall, but there were many other prairie grasses, as well: little bluestem, prairie dropseed, porcupine grass, sideoats grama, needlegrass, and many others. All told, the original prairie held about 150 kinds of grasses. Big bluestem grass grew in dense stands and in many areas was the only species present. It fed the bison herds and had very deep roots that served to hold the prairie soil. When settlers plowed and killed off the big bluestem and other prairie grasses, they unwittingly were a major factor in the dust bowl disaster of the 1930s.

Most of the native grasses are gone now, replaced by introduced species, both escaped and cultivated. The few remnants of the former prairies that remain are being preserved and restored, however, and numerous organizations, government bodies and individuals are involved in the effort. Perhaps someday, we will develop the techniques for returning large prairie areas to their original state, but in the meantime, these small remnants will remind us of what once was, and act as repositories for plants and animals that once thrived there.