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high winds, and continued gales; such grouping being based upon the force and continuance of atmospheric movement. The trash and dust were carefully removed from the cans and labeled as to location, date, length and strength of wind. A specimen label is as follows:
“Harry Davis; open pasture south of Franklin, one-half mile from tilled soil; continued gale, two days; Oct. 10-11, 1894."
In many instances dates were not recorded, but the general season-period is known. These omissions have so affected the calculations that no definite dates can be given in the tabulation; the early or late season-period, however, is fairly accurate.
Vegetable mould, calorized to prevent extraneous growths, was added to the collections and under fair conditions the seeds contained therein were germinated. Many of the plants grew to maturity, others developed sufficiently to reveal their identity, a few were classed “unknown.” The tabulation of results is not as satisfactory as could be wished, but it suffices to show the general trend of the investigation.
The following table shows calculations obtained from fortyeight collections, 1893-4-5-6, taken during
Late Summer, September.
Per cents, by winds .
A single series of experiments can give no well-founded results, and may vary widely from the truth; however, in general it is noticed that breezes and local winds do not distribute ordinary plant seeds over very great areas, while oppositely, high winds and continued gales scatter the seeds widely over pasture and meadow, hill, ravine, field, and prairie alike.
It is at once noticed in the above table that the comose seeds and the pappose and chaffy seed-bearing fruits are dislodged and scattered by the early fall breezes, the seeds of the Compositæ and the Asclepeidaceæ predominating in numbers. The local winds bear, besides comose and pappose seeds, those of the Cheopodiacea and Amarantacee, whose presence is very undesirable economically. High winds do not, as many may suppose, bear the lighter comose, pappose, and membranaceous seeds in greater numbers than does it of those of denser structure. Though the high winds are, far more than any others, the seed carriers, they are also the atmospheric agents that loosen and drift forward many seeds that are too heavy to be borne within itself above the soil surface. The cultures of material collected during continued gales gave very disappointing results. Our adventive, newly introduced, and “out-of-range" species have come within our boundaries by the steady monsonic gales so prevalent from the north and south, over the plain district of Nebraska, Kansas, and the Dakotas. The alarming invasion of the "Russian thistle," Salsola tragus L., in 1894-5, the appearance of carpet weed, Mollugo verticillata L., throughout the entire county (Franklin) in 1892, and the occasional growths of wild carrot, Daucus carrota L., are to be attributed to these continued gales.
A reference to each of the other tables in the series may not be amiss:
1. The October collections gave 20% more of Compositæ, 8% more of Asclepeidaceæ, and a considerable gain generally in the lighter seeds, especially those adapted to aerial carriage; arousing a strong suspicion, which other conditions tend to verify, that October is predominantly the month of local distribution. Gramineæ, Amarantaceæ, and Chenopodiaceæ each gain from 1 to 3% when dynamic data are unchanged.
2. The November collections were notable for a great increase in the Chenopods and Amaranths. These grow mainly in fields and ripen early and late. The increase of distribution of seeds is probably accounted for by this being the month of corn-gathering and stalk-pasturing on the farms. Ofttimes steady winds prevail during the entire month. These two conditions uniting, the tendency is toward a wider and easier dispersion and dissemination than during any other month of the year.
3. December and January show very light movements of seeds, these being buried beneath snow and frozen fast to the surface. Hence these months are periods of little importance in the matter under discussion. Lower latitudes would give data of interest.
4. February and March are also inactive periods. Collections were abundant in debris, but careful cultures showed that very few seeds likely to germinate were contained therein. The reasons are too obvious to necessitate mention.
5. April is the month of active spring work and coupled with it are our spring monsoons. Operating together, no light effect in distribution is noticed. In fact, all things loose tend to fly to the uttermost parts of the earth. Among the commoner ones, seeds of Garden Purslane, Portulaca oleracea L., Tansy Mustard, Sisymbrium canescens Nutt., Black Mustard, Brassica nigra (L.) Koch., Wild Pea, Astragalus gracilis Nutt., and Winged Dock, Rumes venosus Pursh., were unexpectedly present and their prominence in the culture growths showed them to be in prime condition. A few early cottonwoods and willows appeared also.
It will be noticed that these data and compilations are in reference to horizontal variations only. Though it may prove an error, still it is the popular belief that the wind distribution of seeds takes place within that stratum of air that lies about thirty or forty feet from the earth's surface. Let us hope that investigations may soon give us data as to vertical variation, that we may know more fully the importance and service of fences, windbreaks, weather-growths, and hedges toward hindrance and possible barriers of seed dispersion and dissemination. The old adage: “An ounce of prevention is better than a pound of cure" is pertinent to this matter.
[NOTE.—The term "seed” in this paper applies to the general non-technical use of the word rather than in a strictly botanical
It often implies those organs technically called fruitcluster and fruit. E. M. H.]
SOME METHODS OF COLLECTING, PREPARING, AND
CARRIE ADELINE BARBOUR.
Since 1891 our University has sent out annual geological expeditions—the Morrill Geological Expeditions. Three have gone to the Corkscrew beds of Sioux county, two to the Big Bad Lands of Dakota, and one to the rich fossil fields of Long Island, Kan. As Nebraskans, the Corkscrew beds and their contents have a particular interest for us, for this state alone seems to furnish these new and strange fossils. They are embedded in soft sandstone, but it does not seem so soft to the student who works them out with pick and spade, digging through yards of this sandstone. However, after these spirals are secured and carefully packed, and finally reach the tables of our workroom, the sandstone is very dry and readily gives way before the toothed chisel and the whisk broom. Though it may seem funny, the whisk broom is one of our most efficient tools in cleaning Daemonelix. Where breaks and fractures occur in these sandy specimens, it is impossible to glue them together. Accordingly, it is necessary to dig out large cavities and dowel them together, as it were, with plaster of Paris.
The Bad Lands, which are old lake deposits, consist of clays alternating occasionally with beds of sand. Now if these clays were not so plastic and so easily affected by frost-cracks, suncracks, and all oscillatory movements, the work of collecting, cleaning, and mounting afterwards would be much easier. As it is, fossil bones are often badly faulted. Sandstone packs solidly, preserving the bones in a much better condition, making, however, anything but play for the collector, and the task of digging them out of the sand matrix is accomplished only by careful and patient work.