THE NATIONAL NURSERYMAN 
309 
l(‘ss (‘xl(‘iil. PotiK' fruits w liicli wc'ii' s|)ray(Ml iiu(l(‘r tlu* 
sam(‘ (‘oiiditioiis (‘ausiii^- IIh^ inJ uiy as altova' noU'd show rd 
IK) inJuiT. IL\an)inalion of tiv(‘ san)|)l(‘s of load ai’siMi- 
at(‘ (‘olh'clod during llu' invi'sti^alion n'pri'soiitod Ihiaa' 
difl(*r(Mil brands. In no (*as(' did lh(' analysis r(‘V(‘al tin* 
|)i‘(‘s('n(*(‘ ol unusual (juantitios of wali'r-soluhh' arsiuiii*. 
TIk‘ samples wt'ri* all ^ood ^ladc's of acid lead arsiMiale. 
Aeeordin^' to wi'ather reeords and to the t(\stiu)oni(‘s of 
the growau’s. a pcu’iod of dan)p. misty weath(*r piawailed 
during*' and after tin* applieation of tlu' h'ad arsimati' eaus- 
in^' the spray injuiy. It seimis riaisonable to eonelude: 
1. The aeid type of h'ad arsenati'. often labeled “stan¬ 
dard." is unsafe to use on the folia^^e of stone fruits ex- 
eept under favoi'able wa'ather eonditions. 
2. Aeeoi'din^' to weather reports, it appears that dur¬ 
ing the sjiring of this year (1915) (partieularly during 
the month of x\prin unusually unfavorable weatlier eon¬ 
ditions prevailed in the Santa (dara Valley. Cal. 
3. The foliage injury in the orehards of the Santa 
Cdara Valley this sjiring was due to the decomposition of 
aeid lead arsenate by the w eather. 
4. xAeeording to })revious experienee and in aecordanee 
with ])revious reeommendations of the University, the 
basie type of lead arsenate Aisually labi'led ‘dri-plumbie" 
or “neutral”') is a safei' arsenieal to use on stone fiaiits 
and is not decomposed by unfavorable w eather eonditions. 
This is a slowi'r acting poison, howevei-, than the aeid 
type and would not be as elleetivi' unless apjilied when 
tin* eanki'r worms an* very young. 
II E e 0 M M E NI) .V T10 N S 
In looking up tlu' reeommi'udations of (‘ntomologists 
and taking into eonsidi'ralion tin' I'xperienees previously 
noted, it appc'ai’s that there is a choice of thriK* procedures 
for the control of canker worms; 
1. Handing of I nos has been found to giv<* satisfactory 
results. H]ssig may Ik* cited as autbority for recommend¬ 
ing “tn'c tanglefoot” for the control of both spring and 
fall canker worms. 
2. The aeid type of lead ai’senatc' may be sueei'ssfully 
used on stone fruits for tlu' control of canker worms 
provided I he weather rondilions are favoratde. It is 
not recommended, bow ever, for genei’al practice as there 
can be no guarantee of what the weather may be after 
the application of the arsenical. 
3. It is verij sirongUj recommended, w hen necessary 
to use an arsenical upon stone fruits, that the basic type 
of lead arsenate fte used exclusively. In order that this 
slower acting poison may be etiective, it wdll be neces¬ 
sary to keep a close watch of the orehards and make the 
afiplication wdiile the worms are veiy young.— Journal of 
Economic Enlomoloyy. 
Notes from the Arnold Arboretum 
Summer Flowering Trees 
Several trees flower in summer here and add to the 
interest of the xArboretum at a season of the year when 
there are comparatively few flowers or ripe fruits to be 
seen. The most imjiortant of these trees are the Lin¬ 
dens, a genus of many species, the earliest of which be¬ 
gins to bloom about the middle of June and the last live 
or six w eeks later. Lindens grow- best in damp, moist, 
well-drained soil, and the European species take 
more kindly to cultivation in this part of the country than 
the xAinerican or x\siatic species, the handsomest Linden 
trees planted in the neighhorhood of Boston being forms 
of the nautral European hybrid to which the name Tilia 
vulyaris belongs. There is a large collection of Lindens 
in the xArhoretum arranged in the meadow on the right- 
hand side of the Meadow Hoad in w hich can now^ he seen 
sjiecimens of ino.st of llu' species and of several forms 
and varieties, many of the trees being now' large enough 
to flower. Tbe fact that, with the exception of Tilia 
jajtonica which is tln^ tii’st Linden here to unfold its 
leaves, none of the Asiatic •Lindens now' promise to be 
large or useful trees in Ibis climate is surjirising for the 
trees of eastern Asia usually flourish lu're, and as a rule 
are better able to adapt themselvi's to New' England con¬ 
ditions than allii'd European trei's. It is always pos- 
sil)l(', however, that by crossing sonu' of tin* .Xsiatii* 
species with tbe European species ik'w and valuable 
forms may be obtained, for hybrids between .Nmerican 
and European Lindens, like Tilia speclabilis and its var¬ 
iety Molthei, are trees of great beauty and remarkable 
rapidity of grow th. 
SoPHOHA jAPONicA is ill spitc of its name a LIhinese tree 
which has been cultivated in Jajian for more than a 
thousand years, and as it first reached Europe from that 
country was long considered a native of Japan. It is 
a round-headed tree w hich in Peking, w here it has been 
much planted, has grow n to a large size and looks from a 
distance like an Oak-tree. The leaves and branchlets 
are dark green, and the small, creamy w hite, pea-shaped 
tlowers, w Inch open here in .Nugust, are produced in great 
numbers in narrow', erect, terminal clusters. There are 
also in the collection the form w ith long {lendent branches 
(var. pendula)'which rarely tlowers. and a young plant 
of tJie form w ith erect branches (var. pyramidalis). The 
form of this tree w ith flowers tinged w ith ro.se color (var. 
rosea] is not in the x\rboretum. The Sophoras are on 
the right-hand side of the Hussey Hill Hoad, opposite the 
upper end of the Lilac (Iroup. Near them the Maackias 
are grow ing. They also belong to the Pea Family, and 
the better know n Maackia amurensis is a native of eas- 
t('rn Siberia; it is a small tree will) handsome smooth, 
r('ddish brown, shining bark, dull, deep green, pinnate 
leaves and short, narrow, erect spikes of small white 
flowers which ojien here soon after the middle of July. 
There is a form of this tree (var. Bueryeri in northern 
