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larger main roots, very delicate, tine, almost cob-web-like, white, fungous 
threads, which are abundant or scanty, conspicuous or with difficulty 
demonstrable, and which cover and overgrow the organ in many places, 
and sometimes even spin all around it. The great fragility and tender¬ 
ness of these growths is, however, also the reason that they are so easily 
torn off and destroyed in pulling the vines out of the earth. On this 
account, for the more certain demonstration of the trouble, it is requisite 
that the removal of the vines be effected with special care and exact¬ 
ness. This fungus does not possess any organs of fructification, but 
consists entirely of very thin, hyaline, cylindric-tubular threads or hy- 
plise, septate at long intervals. It is nothing but a so-called sterile my¬ 
celium. Although the scientific identification and naming of such ster¬ 
ile forms .is beset with great difficulty, still ,without special violence, 
we can identify the root-mould of the vine with the growth Fibrillaria 
xylotricha , described by Persoon. 
Similar sterile mycelia, which, in essential particulars, at least, do not 
depart from those on the roots of the vine, are found everywhere on 
decaying twigs and branches of deciduous and coniferous trees, as well 
as on all sorts of decaying wood lying below the earth’s surface ; finally 
also on the roots of very different plants, in short, wherever woody 
parts begin to decay. If, for example, in a shady forest we examine a 
heap of broken-off, withered branches or a pile of limb-wood, we very 
soon observe, as we throw it somewhat apart, that the whole mass is 
penetrated in all directions, in case it has remained undisturbed some 
weeks, by fine, hyaline, thin aud delicate threads. Almost every single 
small branch is woven and spun over; and the moister the locality the 
more restricted the access of air, so much the more compact is the weft, 
so much the more numerous are the threads. 
But this observation here communicated puts us at once on the right 
track; it shows us a parasite injurious to vine growing, but on the other 
hand gives us the method by which we can protect our plantations from 
its attacks. In like manner, as into the small branches and twigs, the 
encircling, thin, fungous threads penetrate into the roots of the vine, 
the tissues of which they disintegrate, first those of the outer bark, then, 
later, pushing steadily inward, they ramify between the wood cells, 
brown these first, and then bring them quickly to destruction, and 
thereby progressively the whole organ into decay. It is evident that 
the thinner aud weaker roots first suffer the attacks of the invisible, 
but not on this account less dangerous, enemy, and this is why, as al- 
ready emphasized ,we find the diseased vine when lifted out of the 
ground almost wholly denuded of horizontal ( than) and fibrous roots, 
and entirely dependent upon the main roots for nourishment. For this 
reason, the sickening and decay of the plants, the main roots alone not 
being able to perform the function of sustenance. 
If the subsoil of the vineyard is'unduly impervious while the surface 
soil is very loamy and clayey, then the excessive wet, so hindered from 
