Nevada County picayune., 1889-10-09
A TROUBLESOME WEED.
It Is the Potato Beetles Friend and Fol- lows the Insect Wherever It Goes.

lows the Insect Wherever It Goes.
 There is curious association be- tween certain plants and certain anil mals which looks almost like mutual affection. The catnip, which came from Europe with the cats, seems never to grow where there are no cats to nibble at it The buffalo grass" is disappearing with the buffalo, and along with the settlers who are occu- pying the plains, where the buffalo used to rove, come many new plants, some of them entirely uninvited. The burdOck, for instance, clings tenac- iously to human kind, and seems un- willing to grow unless there are folks" somewhere in sight And there no one can exterminate it.
 One of the most remarkable in- stances of the apparent migration of a plant, as if to keep company with an insect, is the removal of the homely plant which botanists call SoLanunl ros- tratuna, from the vicinity of the Rocky mountains eastward.
 About the year 1867 the farmers of the Mississippi valley began to be aware of new pest in their fields, whose ravages were becoming alarm- ing. A stocky, gaudily-striped beetle, which multiplied at an alarming rate, had begun to devour their potato-vines. Nothing could stay or exterminate the plague. The potatoes, deprived Of their vines, routed in the ground, and an important crop was lost.
 This beetle naturally received from the farmers the name of 'potato-bug. It was found to have begun an east ward march from the uncivilized strip of Eastern Colorado and Western Kan sas, and it has consequently since been known as the Colorado potato-beetle.
 It was also found that in the region of its origin this beetle had fed upon | SolaRum rostratwnl, a plant belonging l to the same genus as the potato. Doubtless the insect had been quite content with this article of food But some settlers planted a field of pota- toes, and the beetle at once fell in love with them.
 Migrating eastward in eager search of it's new food, the Colorado beetle multiplied with astonishing rapidity. In few years it had covered the whole country and had devastated potato 1 fields clear to the Atlantic coast. Then some of the beetles, or their eggs, were carried in vessels across the ocean, and the insect began new career of conquest in the Old World, for it spread over the British Isles and | the continent of Europe.
 All this because some one had planted a potato field in Colorado. But what about the Solanunl roS- hatum, so heartlessly abandoned by it's old friend? One would suppose that, left free from the devouring at | tentions of the beetle, it would have been content to stay where it wasi but i this has not been the case. The weed seems to have set out immediately on journey in search of the beetle.
 The prevailing direction of plant migration in this country is westward. With the settlement of the country, the plants of Europe and Eastern America tend to crowd out the native vegetation of the West. But the Solanum proves an exception to the rule. Apparently it believes that it's destiny is to be eaten; nothing but the potato beetle will eat it, and so it comes East to find that insect. It has spread over cultivated lands in Texas and Missouri, and last summer Prof. L. H. Pammel found it growing at Watertown, Wis.
 Wherever it goes it is a troublesome weed, and seems to increase in size as it comes eastward. - Youths Com panion.