The Pioche weekly record. [volume] (Pioche, Nev.) 1877-1900, 1894-03-01
BOSTON ROOTS OF CITRUS TREES

BOSTON ROOTS OF CITRUS TREES
At the Los Angeles Chamber of Com
merce on May 3lst, an interesting lee
ture was delivered by Prof. G. W.
Woodwork of the University of Cali
fornia, under the auspices OF the Farmers
Institute of Southern California and the
Los Angeles Horticultural Commission.
Mr.. Abbot Kinney of Lamanda Park
occupied the chair, and introduced
Professor Woodwork in few we'll
chosen words.
"The subject for discussion to-day"
said Professor Woodwork, "resolves it.
self into two diseases, which are the
principal ones which will take our at
tention. These two are of the greatest
importance, and are sour root, or rotten
root, and the crown knot or root knot.
"In considering the question CT these
diseases, we must first become ac-
quainted with the physical nature of the
tree. The life of a tree depends great
deal upon the water-carrying condition
of the trunk. When we start with the
lower plants we notice that they re-
ceive their sustenance and their mois-
} ture and give lit out over their whole
surface. When, however, the plant be-
, comes differentiated, SO that there is a
J portion in the air and sanother in the
, ground, the latter becomes the chief
source of water supply for the plant.
This moisture, passing up through the
stem of the plant, is given off through
; the sides of the stem and the leaves.
When we consider the larger plants or
: trees, we notice that their stems OF
: trunks are protected by thick bark,
which keeps the inside tissue from the
, atmosphere and allows the moisture to
pass through it from the roots to the
, leaves, from which it is evaporated into
the atmosphere. This bark, which pro.
, tects the trunk of the tree, has no pores
and effectually prevents any evaporation
, through it, as in the lower grades Of
plants. Every plant is composed o.
minute cells which are full of moisture
J These cells on the outside OF tree dry
up and become filled with air instead o
moisture, and thus produce the bark
, If the bark is removed the undertaking
cells dry out, become dead and impair
their dried-up condition inward until i
affects the inside living tissue of thu
tree and endangers its life. Anothe
form of disease which may endanger thu
J tree in much the same way is that pro
, duced by certain minute parasites
Every organism is composed of cell
> which in living, healthy condition viii
be taking in food and exuding refus'
matter increasingly. Ii cell is in
perfectly healthy condition it can, b,
the force of its exudations, keep out anC
q prevent foreign cells from growing upoI
5 it. Ii not able to do this, the parasit,
{ once in place, continues to grow ant
eventually destroys the cell in the SAM
r way that the healthy cell would have de
stroyed the parasite. The germs foun'
r in rotten root attacking trees of Jh
citrus variety are the same which liv
among all kinds of decaying vegetable
t matter. They are partly bacteria, al
though we have never found one form
always present. We find great mum
Q Der of forms OF these and of fungi, an
r all OF them are those which occur in de
caying vegetable matter. The means b.
/ which this disease can gain entrance t
t the tissues of tree are, probably, frs
where the bark around tree has bee
accidentally injured and then expose
, to dampness, SO that before it can pre-
tect itself and throw out new bark tn
g rot has entered through this dead an
: decaying bark. The second is wher
organic matter undergoing decay, as, fo
| instance, where tree has been jplante
! where another one formerly was located
or over an old stump which yet remain
| in the ground, and whose decayin
matter thoroughly impregnat,s it, s
5 that the cells Of the young tree, by thei
: secretions, are unable to throw off tn
| germs and are compelled to succu NIB
their inroads. When these parasite
once get to growing well they can, b
their secretions, kill the wood as fast
they increase and eventually kill this
/ portion of the tree. The effect of thes
dead spots on the root or trunk of tire
is that every dry spell will dry out til
, wood OF the tree ard make it almost lik