The Potato Industry of Colorado. 39 
When the plant stem was split lengthwise, it was found that the 
sap wood or vascular tissue of the plant was discolored from the 
ase of the stem to some distance above the ground line The riant 
was often blackened from the vascular tissue" out and in some £s 
easTand it was f* Z .w'' Investl giation was made of this dis- 
Fusarium Ltif d at ? was f caused by a fungus known as 
riisanum. In the cross section of the potato stem showing the 
PLATE XII.—Fusarium Hyphae in the Ducts 
vascular structure of the stem, the hyphaToTthiTfunguT^ shown 
circria n t?on C o 0 f SS th 16 f l, . spaces 1 - A PParently this fungus acts on the 
alfalfa do in a tile drain.f “ r °° tS ° f cottonwood > "«l°w or 
as well as stopping the°c^rculatfon Un T S oa? e f i° ther damage to the Plant 
all parts of the State show that fUl - exammation of fields in 
more or less. If gro Ar S ^ a J most ^ays present, 
sionally find plants that appeal to be mati ng eariy ^Thpv ® 7 A ° c . ca ' 
yellow and showing signs of dvina- Tf Z ! ? § early * They are turnm S 
you will nearly always find theAw ^ Bt ? ms are pulled U P a *d split,, 
stem just outside tTe pith tissue ^ SCOl ° red area running up the 
the plants are young and in fiplriQ « n dlsea ® e 1S m °st noticeable when 
fact it is quite probable thJ? n t * P ° tatoes follow Potatoes. In 
toes follow potatoes and alfalfa t dl£fere . nc e between yields where pota- 
due to Cravages of this m t ? e Greeley strict is largely 
Two preventative measures may be adopt^A A^AhA°f th j S disease ' 
crops so that potatoes will not follow not AoA A’ £ 1 of rotatln g the 
the seed by exposing to the light and air A that ?£ d the Sec ° nd \ cleanin S 
will be largely killed and thp tnhcr ’ a Gla ^ s P°res of this fungus 
whole seed is always desiraMe The P la »ting of a 
development of the disease is fa a l bls ^ lsease ls liable to occur. The 
Where” are porous and notion y , T ?. 0 " s and high temperatures 
Perienced from this disease lltUe tr ° Uble has been ex- 
