Insects injurious to mushrooms


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Insects injurious to mushrooms
Physical Description:
Popenoe, C. H ( Charles Holcomb ), 1884-1933
Govt. Print. Off. ( Washington )
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Resource Identifier:
aleph - 29683247
oclc - 28158748
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Full Text


V ~
5 I.I. I r

L 0. HOWARD. Fntionwmolo and Chid of Bureau.



Enlomnlogi{fl Assistaint.

*A ,HI I- TI=- I- u4I6 [ r,sW[%T FCl 6 'l j 'I1. 1 I l .l

-; .
LI -.

Dr N





L. 0. HOWARD, Entomologi.t and Chief of Bur'au.
C. L. NIARLA T, Entonolugi.0! und At'ing Chicf in Ab'cnc' of Chief.
R. S. CLIrTON., EJt'cutire .I .ki.-tyut.
W. F. TTASThT, Chief Clerk.

F.R. I'il ITTr..DEN, in( harg'e of Irm k v'i up a,,i' .,t,' .,i I,'rOtlr t inl.l t in resligat ions.
A. D. HOPKINS, in charge of forest insect inrc.xtigaltions.
W. D. HUNTER, in charge of s.auth(rn firld vrop in~c t itreaigationi.
F. M. W l'ITLR. in charge of cvr'al and forage inx'r't int-r.stig1tiruils.
A. L. QUAINTANCE, in rhargc of deciduous fruit inxr'rlt int u._ligallions.
E. F. PuI1H.L.jS. in charge of berr culture.
D. M. ROGERS, in (h lrgc' of pr( acting .spread of moths, filtd work.
ROLLA P. (A'RRIL, in charge o.f vilituriul work.
MABEL CLu'URDn. in charge of library.

F. 11. 4_uIIITTFNDFN. il (.bargr.

H1. MI. RUSSELL, C. H. POPENO-. BILi.IM I. PA.%RKLM. 11 i. M.NasH, M. M. HIGH.
FRED A. JOIINTON. JOHN E. ( viF, e'ntoioltgicil a.,.%i5lul1ts.
I. J. CONDIT, -,.li, boraffor in (Califor,nia.
W. N. ORD, c',,ila!,,,tifor in (jr p~m.
THOMAS 11. Jo.m:s. 'ullaborator in I'orto Rico.
,%.\RION T. VAN HORN, PAULINL 31. JO1INSO.N, AN.1.1 .M. BALLINGER, prcpar, tors.

CIRCULAR NO. 155. 1u Otor 6, 12.

United States Department of Agriculture,

L. 0. HOWARD. Entrmul,.Ao%. and Chief of Bureau.


By C( 11 P'.ri %.I.
I.. t,,/.,',,,i'...i. *i ..l<,
Cultivated iiiii~1n-l>'ii-. ,,-i,,i.,l]y duriri,_ warm weather, are at-
takti I lY -everal species vif insect pests whiwh frequenil deIstroy
all fii 'e crui,. or so curtail the production s to mIake the indust ry
iproihilita lth. .\llioj~iil, this injilr. is at
tinie- ,t'riol ii-. little interest has been taking i
hv elit oim il', ,-i-I in the matter of itc con- /
tri'l. -,, that I her't is |. r.iii,> llv- IIo available 11
t'trioiiiii" Ii l';I l tiI' Ion the ,l, ji, t. T hi
.in'i l:it i ,,* f a Ircliiiiin:iry nature, as the
ifvlt'-i i iii i ,,f all insectsin njurious to ;t- ,dt
mniti '"'Iiill, 111.n1y not -be i ,, i' i r .ome Ilk',
tini ..
Tlhu ii-,rle which ;i-, .ill' attack culti-
vatei, m-lr,,ioiin-. and those of which corn-
phl iiint. .ir llost fri ,ii,' it ly .l i.. it. i\ 1.'
diviiled, runiiullY into four 0 -q -. namely,
'lllih'olll ll~it _~ILPIt d 1 '1 ril'll l.*I hi-. anid Vv. 1.-A ntuu hr oin fly. .lphi-
l,l ,i"' l r-.. -. Ii,,-. the rn i,-.',,- I are the 1 h1 A e ihirti IriM l.
M~u h enildrged. ', tlaUI.)
ma,.-I ieri,'r.illy injurious, thi e iuitecs I'llw
in ,,rdhrr ,t imi) rtance, i,",i1ii,. to t,,. ,itlli. ,uliV ith w hich their
ernili,':ii,'ii i *,ir'iilili-l]id. and then come -"'liiL ,; Il' and -ri,,l,,"
in I Ie irdl r named.

(.S'' i,'- mu/tirta I ', .-i et al.)

The inj,.rinon- forms commonly known a- .mus-hroom il ,-,.it- are
small I liii i-ll or y,'ll-awi-1 Ihi It? 1. I. "(L', ,L.- usual I ha: il., black hl eads.
5n9VS:-- -ir. l1.,-1-12 1


Tliey are the y ,oug of certain small flies or "gnats," two-winged
and mostly black in color, of several species belonging to the fami-
lies Mycetophilida, and Phoridap. and to the genera Sciara and
A.phiochaita. Of these the species belonging to the genus Sciara are
by far the most common and injurious of mushroom pests,. They are
minute in .,ize. mnea-uri.g about three thirty-seconds o(f an inch in
length and about ,ne-eighth inch in spread of wings. They are
smoky or dusty black in color. The species attracting most atten-
tion as pests are Sciara multseta Felt and Sciar'a ,grii-bi Felt. Both
species are, like the other mushroom gnats, rapid and prolific breed-
ers, especially during warm weather, frequently occurring in mush-
room houses so abundantly as to darken the windows. They may
be readily confused, however, with gnats of the same genus which
breed in manure or in greenhouse soil, and determinations should
always be made by a specialist.
Another common species, Aphiochleta albildhedtcris Felt (fig. 1),
superficially resembles the preceding, and hais much the same habits,
but as yet has not appeared to cause so much damage as have the
species before mentioned.
The life history of one of the mushroom maggots is about as fol-
lows: The eggs, of which each female is capable of laying nearly
1,000, are generally deposited at the juncture of the stem and cap of
the mushroom, or in the manure or soil at its base. In a warm tem-
perature they may hatch within three days, but in colder weather this
time may be considerably extended. Upon hatching the larvae bore
at once into the stem or cap of the mushroom, soon riddling the cap,
and causing the breaking down of the mushroom in a short time.
On account of the perishable nature of their host they pass through
their transformations quickly, the larva? feeding for from 7 to 10
days, by which time the entire cap is destroyed. The larva then
enter the ground, each spinning a .slight silken cocoon just beneath
the surface, and pupating. The pupa stage lasts from four to
seven dnlays, after which the insects emerge as adults, soon afterwards
pairing and ovipositing for the next generation. Owing to the
immense number of eggs deposited and to the short life-cycle the
rapidity of their increase is remarkable, so that the presence of only
a few insects in the mushroom house at the beginning of the season
may result in the presence of millions after the beginning of warm
weather, thus effectually preventing the cultivation of mushrooms.


It is evident that in the control of the mushroom maggots measures
should be undertaken early in the season for their elimination from
the mushroom house and precautions observed against their subse-

q1 llfl t lit I' ll it _'. iii *,i -I ,,i ii I .1 .. ii. I l'li -I- I i I n 1 I '

iif ll''b t i. 3 l' i rf l it'.' i l It I ,,-, lie ,i l''l -, r i ii', l I.
tiw irt ifi. '.I i .* t ii I ill t* i *Ili l, .i If ti n ,I Ii .I I I ,, ,* I
g n f ^t I i ,e I I t l I i t I'l ;I .,_,v I I 111 I!i I .I, -, 1 i 1 1 1 11 :1_ ,, ,,l I I I'

b l a rln n 11n- 'I h e 111. 1111 1' ,U, '" I f 1 1 .. 1- -, %I-, iI I: r l I 11 l '... l,- vl ',' If ,,II n"I
1Un" 111,1tiin_,, Li 'r il.'in llL. i "ill Iil i-l \ .l -' ,,i .' Ii 'iil ,I l w -l.' 'ilii
pilloi.s, llJ l i I II il v ri II iaII I I'I i l ,, ill! 1 W ii l'l I-" I l \i rt
iOlsilt. i .lt't li I ', llr. I i -e. l i.i I, .1 -I, I. 1 I, I I I I 1 .1 1,. iiil- rlii
ti ll' il re o f 1 Iit : ".. 11 '11 1 1 1 1 l I nl il I I I I. I I I I I I l, '

iS ils, ]i l'r t l i tll 'l f. fi ill I I iii Ill I I' li I x l' I I [ it i- I I I I I lit' ,'11 ll -
t llC,. i. 1 'h <>l I- lll li -h ,il l ti ,i l I v I I 1 1 1 ,, I I I 1i Ir r1- I

1.000) Ctil)i. fei*t ,If
spactl ani -li,,iill -'/
be evaiVpilat' /^
shallow ji:i11~ 1- { --- ---- {I
p lI c'1 1 in t i] v
higlhett |it ) if a_ 4
the li ilIt'. Ilt i- 1
very iiitl:iiiiinn ilillt ---- ....
and eve'n v bli )-I, )- / /
Wihen bruiir i il tu ii. -. , .. ... . '
contact wilh liIrn -,, .
or1 -pilrk-. illmi t car' -lImile I, l' i-el ie fii, hi ;,.iii i \ lit
in to ihe llir I 1iil i xl-, il i'iii-il Illi' -Ir ',rr- f I'lii i': L; ,..
O ne of tilt h I' -1 ii 'litn l- t''r ilt ,h i i.l, i i i ,,l1' ili ..ic ili ,,I iill0-.
in tht,'ir <'Til 1'' ic't ii, i i-liriitii i l,,i-' I- 11111111 i i. i ti 'lii ItI l.;e ',,
1or nir,,liI fiiii ii i il -i' l i1 i'' I-1'l it iI \ iilt',i, -I'-. 1 li,- -le. i til
be us !ed iln n; ''(iral'iiit' ii lli ii lir',- i, ii 'n- ii,., l, it, '-i n ili,. p,.i ki.i,.r-.
for a n ie ili iir i ai iu1 :i v I iii i li, ii.' -, 1 ii i I II l i. 1.i, .iI.l ;ilp-
p li',l oli('1 a \v i'lk illi iir iir ilL,' Ilr:ilriiIL, -.,-,,i li, iii' d iiiu -lii',,,,ii I.emI.
th is iletl il l lit I- ,'.t -4.-ii ,1'. v -I' l if n 'll 'r i ll, lii llil,,i ,,f li,'-
that very littlle l:aumai '. if ili\' I r-i lli',Il IrIni llit lI ll ,'.
F ilnii iali tn \ itli ii iVc II I li e i l-li-tiTI.. lic' 1i,,, l.M r 1 \ ,ill l- 1,,.,I.
is alsie etT'0t-ti e i._ in i I,' ml-lr ',,,,liii II.I'_"'lI i f laizlii in i ill'. !,it
tobacco fiiiun ii itin liti vy l't e i' -iii. ,rciIl -i:iit'.ir'I f,''r tilt- i1-,
1Trlr pre',p.irYln -f nio-,til .n l t l, l.r i i. I. -, I, i i l !1 i '.at
Ro ll ild -.' lii-o :i- l ti-i I'r ta iaii.i;. .j

N S -'. 'I. N I 1 1' 1 1 11 ., 1]4) % \I I' I NI 1 1 %1 .

(Tyroglyph u. lintneri Osb.)
The mushroom mite (Ti!roglyphus Vintrwr Osb.) (fig. 3) is a
riinlite, soft-bod ied mite, smooth skinned, and white or whitish in
color. It is closely allied to thle common cheese mite (Tyroglyphus8
sIro L.) and resembles that species in appearance. It is. if anything,
more prolific than the cheese mite. becoming at times so abundant
in mushroom beds as to cover the surface o(f thle compost, and when
present in such numihberN i.-, extremely destriuetive. feeding upon (lie
mushrooms in all ,stages andl penetrating the beds and destroying the
myvceliunm. Indeed, in one case
k ."K observed by Mr. August Busck,
K ", / of tlh: I'tre,,1,' the mycelium
,. i ,,.. / ',/ was de-,troved as fast as it grew
^ 's^-' n. ^ ^ front the>"P'"
/ Thli-, -pecie.- is undoubtedly
\" .\/"'" thle cauve in manyv cases of the
.s y '. /'<.,/ .^ '
,--.'.--------'--- failure of thle spawn to grow,
---- ---- '* p <. --- which i,. likely to be attributed
SI \ \.. to poor or weak spawn, or to
7 "'-' defective cultural conditions.
SI The minute size of the mites
h. ,,'" / causes, their presence to be little
(<-/ \ \ SUSI)e(Cted. aind the failure of
7\. "the spawn to protduice mycelium

conditions favorable to the
Si growth of the mycelium it is
I I' ", possible for thle mites to increase
i to snchi an extent that the en-
/ / i tire bed mayI be killed out.
Besides the injury to the my-
Fio. 3.-The n'.hilrnom ni, i T.iofJufyphus celtini, init-lhrooin- i mites cause
lintneri). IlI.hlyk nI.:,ir.i'd I From im Iage to thile fruiitilln bodies
Banks.) ..
bY eating into them. distorting
or dc,-t 'roving t(lie 'yotn growth. In the more matt re mushrooms the
mites inv 1'e found cliteredl in groups consistting of individuals of
,ii,.nnv -iz.-. itvunllv liiddlen in the folds between the gills, where they
burrow into the ti-ie annd rapidly break down the caps.
No direct iioi-ervati,.'i-, -;iring on tlie life history of this species
have been ma,,d.. but jilgiini. fromn that of related species it is about
as follows: ThIe egg-. wlhiclh are lar.ue in ),'op)ortion to thle size of the
mites, are lIiil in air allIouit tlie mycelininm of tlie mushroom, or on the
\ t' l'ul .', lBullr Entl L" l ipT .%gr. p '-., 1i04.


I .S '.i It I l N I I l I I i M I .' I % ,I( I; uM -,.

tu-ttri-' ir \ Ir .-'^r l M iin^. lii l 'i X I i ail\ uni Ifr a1 d ii 11 ~ n11 11 1] to
th I lit Li ifr i fo fII .-r Ie
tll '111111 i li II li, I i lll fl ii i < .11I...- |(l li ,f I liN, f'- -,, l |t I.
rutth ily A f llI iin tr 1ii 0-111 -1 11 111 If I(.- i Im~ 1iil r |4.. 1 1 1 111.
11iititi \ i i, "i til liu it. l il i | il. i i ii i iii,.- IlIr, ] .1 1,.. I,,i\ .I I I ly
0( I ll liii jimm'rri t uti t II11111Iine' Illul i -i l| l > i lIr lii-' -. rl.1n1n>nI I .1i q. 1.1 | n |ilyk
as if b%?, I -g'W. I ,-I tii- ,# < i I, A l I il t i I, 11 -u iI .i ,i .,i- iI ,1
tiolt SI niu i',t ,ll I I II I :l lli I I\]iml' I il II I I I -..i i ' 1 lii.
ti'm i" tI tiiiL 1 a i I li.It u. i tlir lj\ jI ijii I- 11 ri "-Ii., l..i \ :i 1i- i
(.lrlC ld. 'lli h- t ;14e' Ii'l il(ili L. I.' I (. i -. l [ : 'I I.-i II I li r. I. iii l,

sT yrf' ly[ p itl L I i% I. Ii i li l li i mi le m I ih iil -I I Ii, ii l i-. In rilm l'.:is
T i ttilt' IItil \ l r lil, ,1..rur ,i- I, ll-n- 11 .1 1 .1 ,111 0 hii1 i A i i I .1 l u-I
Surlif'ac oftlirI lml:lmt tilt, nit' ; l'.il. >-mI l .i. liliit- I i -X r ...t l,-i\- tiili,-;I ,
ofll .'tKI( I e 1 t'n1Iit'- 1 ir ;l1 t. lt' Iti l i f' I, 1 i, u n- I ,I.. II 1 .1 i i- I, 1.4m,.
no fs ,it i liil t't ld-te'- ull i ijil t'V I ii -' i ',W I ll 1 ii. a J -I [-
ab 'il i r m L' t' i- t ln liu lr -lt I ti it'-'t l t.t l i', 'til i-f ni ,- II --, I tl ,,- l in .l -1 ,
findl .04111 IWt'O HICH' ill lll ll l-l'r fi ll'' )l |l% i l|i ll- -1 11-1-, llir lt, l lr l .6 -
no foo(> ;aw l caiii vi- fit n' i ltry l'> fll-r %k-r i l\\ l. |h 1i rril If. li
peclie l iti '-. .. ( l in ii- l il m .,u ," ;it -. i'- -li ,ili- l lh r i .ill ,il irn:in U i)
new localitiv,- ,III,] i, '11 MailnV v'ir-t1 ]Tv-|>ii l- lr11 I t.r i- ;ii rir ii 11
loctilitit''. fair fr'i rin r1'<., iu ni-]Y iil'.-tm t Il, -.
In ailutlitin ti tli \v-l' iitt'utihiut'tl :ilu \c. 1lir) u %nilti tii\ VlII ,Hi
Dcct'e-', tio lII?-l ih I' Ii linui-'- in iII l''-t 'il 1',riIh"Ih ,r I. 1 -il \\i 1 I' 'iiil
illnfestti lth l..t'-'. I |(, ''Itr. llt' r.I'e ;it I l, ',it if liun lli l','I l .l- m l il-
nlul r t hLke., lil,'t' tlni'ii li ..d t gil im y tf li'-mall In \\hh Irt nl' .ivr ,'iu(
n tlIs vlro ,Il htmi-t|'. :iltIl \\llu>-i, ,'-nrIr lli li;l 1411l 'l. i.i,_m ,t li, ,nilu
froin one' iim] -v' i, ;liii illtt'i.
1: ll D1H11t

Little t'c i lit' ',tinmiiriicrili' l fi lr' Ilu, '''in? r 1 ilwl imiii- 'l iii Ilte.
after it hI,. 'nli'e' lit-c'm i i' c'-tiil i-mi li'Il i :i Inl-i,- ( I IIiI I, i l, .ili-
.en t' of If l't'.ltllll'-p"'il'l'1- i i I-ll l l f ;lt.l,'t'l l I\ l11. l i illiii'.lil -lilt iI'h
f r, the ciit l'nl if ln' ith r lirl-lu iim llm |ir-I-. 1 l0ii1' ;i | i,',l[,lI- .f
Ull Iph1 ir. tollpii I, Illl-I. ;l d ,I ,tlluir l ll r r,4 i, i il i ,, Irl ,' I,. i
Seeni llli v Ii lt r,>V iIi-l i tlI ili'm i li'lll'll tin lIlI Inll,- I i1- ,lit ,if
(lie liiO .t -tlillu l ,lmi plet'- %%iltl \\lli li % v ll; I \i It i I,.ll i, 1 Ili'- 11 ] i',,ni
culture, and ll lil I II'r hi ii,.irlit iilim li. 1,mliii- Illl : iin'-l .u il i.1iilmr'
thilt is. 1i-e 1 fillr tilt- Ivil. 11 1ll,11 i llI, l.\ p up ii- -I., I," hl 1 1l1,|l1,4 f
prolonged u piih-]i' ii iol f \ii-lilit .11111 u- luki, n i li ll piiu n ll i ll O i lIt l-c.
for ain inliniiltd J lJim .%% \ 0it 1ii, i il, ..l li. "l'l l l\ l ii,.:i-pir,. liit,11.'Y
thnt miay 'be ('coimi-.idtlri' l r;l' til'-. f irll'ViilIlIll.
lW hen a 11o01m lt"'olnn'll .- iliif'-ItI. ;tll o ilm-.i -l)lmI- l< I ,iilwit l', I
w ith the tlm ost c re. r'iiirov l I t[i I.IIi- l,. ll.,. Ii li 2 ,li7ii,
i I'r[,," 1' S \ir ,ii ,. :%. .I I'i


fected by drenching with boiling water, or it may be hauled to a dis-
tance and spread upon the ground as fertilizer, or it may be destroyed
ly 1bur1ning. The ground occupied by thle inmulroon beds should be
lli.,riigldy scalded, and the woodwork of the mushroom house treated
to a wash of creosote or crude carbolic acid. either of which is distaste-
fuil to the mites. After complete disinfection has been accomplished
the house should be screened, to guard against subsequent introduction
of the pest by means of flites. All manure forming the beds should be
steamed, according to thie directions under thle head (of mushroom
m1aggot-. Care should be used to purchase spawn only trom unin-
fested houses. With these precautions it i. unlikely that trouble will
be experienced from the attacks of the mushroom mite. Close watch
should be kept, however, for any signs of the presence of the mites
in the beds, and the compost destroyed upon their fir,,t appearance,
as it is impossible to secure good results with mushrooms when in-
fested by these mites. All applications of suffi-
cient strength to destroy the mites are likewise
SinjuriO,, to the nimshroom,, and it is futile to
attempt to control by any artificial means, once
the mushroom bed becomes infested, as the mites
are buried so deeply in the compost that no insec-
/ ticide will reach them.
/ .A predaceous mite belonging to the Gamasidae
S, freljiently occurs in beds infested by the mush-
room mite, feeding ipon the latter, and at times
Fr t.--A common in- he_.o(minmr so numerous a., entirely to wipe out the
jur ious springtail, ? e
Achwcutes arma- pest. TIhe gainasid may ie known by its longer
turn. Mu c ah e legs and its manner of running swiftly over the
larged. (Original.) t j
compost or the mushroom.-. Thie writer has seen
cases where the ganima-id has occurred in such abundance as greatly
to outnumber its host. This predaceous enemy does not feed on the
mushrooms after the destruction of the mites, but seeks other feeding
groumd-. or dies by starvation.
(Achorcutcs arinatum Nicoleh et al.)

At times the surface of a mushroom bed becomes alive with minute
brown or black insects, whi(il, when disturbed, leapl) about like fleas
in an extremely erratic manner. These are known as springtails,
since the -prinlgiiig is performed by the aid of two short bristles
situated on the anal segment of the abdomen. These insects (Acho-
rentes ai, fnim, see Iig. 4) are present in almost all manure, where
they feed on the decaying vegetation present, but oni occa.-ion they
niay become quite injurious in mushroom 1iounes. A correspondent

iN I:r [', I I':I' -. T MIN l iitcidii -. 7

in St. MIun, n..f [... r 1.iri that in of his 1iuh11mt houses I bed
l.'iO ','vl i, ,.n~tl, had Ix'eii complehtely d+s(,,, .,l rlI, these l,.'- ~. whiich
atli kc, l tIn mii-h~r,,,,iii- as fa0 t a. t ,'r\ ,i ,,'.11 T. ,',j , ,I 1,,-.
t ,nn d lt iii' them il l tIl' use. The method ,,r+ attack
of Itlii- iiL-.e't i- to f',',l upon the ufr ili ,.._, Iodies, i of tlie i nlr( n-II,
d(i',trhivy n...r l, th t e ,'il. l, t nIl tI cap. IIi(u-lrril? ma- lie found
ehi'+l(rt',] iilnIn ft -.ii;z1_T'1 Iitlshrootm litiel I>HI+^I'L' l i ._',- c+uvities iln tin
rvills. It :lIlc:I'r. to be a habit 1 ', thI e f inI I c[I to r'ii i '. it in I. II-I
numilie'ri <'TI ,:ips w]hichl have eeln .,Iil'_ty iujn1,1. in ,i hich ca'ee
th tin' injury ,re not coniinued. I'i tl-v octin in lIn.'._, niinber
tneu nre li kely to attack <'\cri the li i t n ,slri is. 1 I i I' II :.v Ited

In.i-clt ,>1" tliii- rniii pa'ss tir ii ii- L i, Iirviil tr i ii ', I, it nl. the
forin 1 1 f tin. iin \ y hatched I,,ii,,. II'i r" siniliar to that If l,,' :;Iii.
T i vv ; 'e Iilni likely to be i IIjurioIsI ill thie salie ii1:inner i ll.llii],,ii ll
thiir life hiitry.v.

The remepdi; ~lmnwnsures ;ili[ .lde to thle controlil of t~riiiL l.ii1- are
to a lan' rre ext ent preventive, as these i serts are som-what :ll ,:ill
to t'ontlrol wlien once established in a mushroom Ied. They are ,11it,.
resistant to tilMiaeeo powders. ibut aipplieatiIIs of IhIatch or [i\vr. i,-
rum to the lied, iare productive of some i\',. As they 1111 n1ly con-
gregate ie':r til, surface of te ot beds t',,r i ]I-.. tion with hydrocya1nic-
acid gns. ,cordi n, to the directions H _i- ii in ( 'irreila1r 17 of thiil
btiiren,. will prove W',1,i live in fr.1ii ii their numbers. ThI, cyanid
shoihd li e u-ed at a -lre.I *rjl, of from 3: to ( ounces to each 1.1,,, cuIi c
feet of air .-'p:I-c. which will not prove iijurious to thle ill ,li,,iI,.
By w.Iv of pirc\ .iilioi,. -1i,"in i ,_' aill manure, a1s previously -,i, -
gested for other -periit-. will destroy i' ril,_'l:nl equally well. WI, r.
possilhle. it i- IbIttcr to -r.','", the mu-hrooms u at a t'ii, IIratlire ,,f aloit
5'.' I". tlhin: lli..lirr. as at low temperatures the -wiiir,'t iil- lbreel
mit'h hle- qiin klIv. DT-I I-iL the tops 1- the bels with powdered lime
is also .aid, i liisweour.i', attack lI v i, ri ,Is.

S Ii'i",ili l'i. i 'M ift and ".' t.' i i ll)
Conidlernl'dle injury is ifti-ii accomplished to mushroom l.,l-
through t It attacks of -)I, l. -Nr.,yish. or slate-i ,,,1 c.lreatures bear-
ing seven pair- of ler,-. Tit-, creatures aIre not true insect altl.,il.l
know'i variou,.lyv 1 the terms "worodlice." sowmus,Ir. and pill, '.-.
Two pecie.. the greenhouse piilli-, (Ir,/ F1'.,/'. ,,, La-


treille) and the dooryard sowbug (Porcelio laevis Koch), are illus-
trainted in figiirc, .',, 6, and 7.
Sowbugs live in damp, dark places, such as beneathli boards, in
cellars, and in the cracks of sidewalks. When disturbed many spe-
cies roll up to form a ball, lying quite still until the danger is past.
(See fig. 5.) During the night they issue from
f N their hiding places to feed upon decaying vege-
table matter, minold, and other material present
in damp soils, although at times the roots of
S plants and even the green leaves are not es-
fThe young are carried about in a pouch,
formed by several modified anal plates on the
abdomen of the female, until able to shift for
themselves. When releaz..ed by the female the
young are similar in appearance to the adults,
although much smaller, and are likewise cap-
Fir. 5.-The greenhouse able of damage. There
pillihL, (Armadillidium
ruigare) extended. IS probably Only one
Much. enI.rd. (Orig- generation annually. the
inal.) L
young making their ap-
pearance in the spring and requiring one sum-
mer to reach maturity. ..
The destruction occasioned by sowbug-; is
due to their attacks on the caps or fruiting
bodies of the mushrooms. These they attack 6- g
., ., , ,, . FIG. 6.-The greenhouse
while quite small, destroying them or injur- piliiug (Armadifedhum
ing their appearance. rulq rej contracted.
A lMuch enlarged. (Orlg-
They do not, as a rule, inal.)
attack the mycelium,
h ^ but eat holes in the young "buttons, which,
on the completion of the growth. become much
J | ~larger and disfigure the product.
,'f Sowbugs are. more frequently than at first
S might be thought, carried into the mushroom
house in compost which has been allowed to
stand outside. The heat of the manure is
relished by them, and they collect in numbers.
FiG. 7.-Dooryard sowbug remaining there thiroughliout tlhe growth of the
(ocllio mi). Much
e(laredo (rignsa) Muchspawn, but becoming injurious with the first
enlarged. (Original.) L
growth of the mushrooms. The writer has
seen -owlm-gs collected in manure pile.; to such an extent that numbers
aggregating a pint or more in quantity might have been collected
from a shovelful of material.

iN.l i l l\ II 1:1111 TO I I -V IIi 't\lI. 9

Where the mushroom housis lt :nall i nl iti |....-. 1-' Inateri-
ally to reduce tlhe mi ber- 'I'ir. lirii-, nii\ he visited at ]ii hlt. whlin. In lhe aid of a lantern.
inm vi: 1r- f -,mi,,iii- may be otvcn icra','l ii- about on the earthen
ca-in (itf thie lleds and 1ii, ., the 1 oIl' 1 ., anIJI Ilppot of the I 1enche1 .
The,'- may Ie 1l, -tr \,. I withi a IImall ; oodIn I' iII.'.
It is also possible to sec re -Ii ... re-ailts I,\ I"'1 'n" 1hot w:itvlr .il, ii.
tlie cracks in the hoards and in otIher \Il\us vwl'e the iin- n mvy
Ie 1,ri-,.al.,I 1hv day. TI'l i- i ll i, 1 it in inI:All h t l i-hiieiits. hut is
S0.1i hv\\lll illlii'th ll of *l(i|i'li ,.,I i ll:l' luu -?. In Su 'h a I -I.
fum i.,ia'rtiiin, with li lri,':iriir,-acid ,- is ;in live r.Am1'"dyV. Treuat-
ilt-nl with sulphur dioxid is also, I,..tive. lint Ci1- reiedy should
he applied I a fir ti-he mushroom crop has ein hali'vested and the coim-
post has beei removed.
A llotiher method is to cut small pliecev- of raw potato, plasteri ,i the
WtI .Ilrt:';ice \itli P\arir. "r,,'ill. and layili- them albot on thle beds, in
the localities ail' uv. ,I by the ,-,li -I -. TIl nw:llI is |'rr .il, lv
Su'cIel .-fil in entirely iriil-ii houses of thii pest.-


.\iliL r other injurious I'riii,- which at timie- aIttack ii,,-li,,'iii,-.
ecrliiiu crickets are reported as K:ttiWI._ into the ,aps of tihe imush-
rotni-. On the l':irili, coast a species klnoin -. i 1, il1 -ll" as Ce,-
/iii''/;1"" 1',H '.'* i' T oini. lhas been reiiorted as i i-iit extensive
IIju ry to .l t i tl ile1 nmushroomn beds.
Thie remedies ti'r crickets in their injury oui occurrence are the
?-iune as tho.e recommended for -,'1i,:.- in a pr evious- se(t ion of this
ciriular. 1',,i.itii,- and carrots may be minced before .itl i. ... the
I'1iri greii. inll order to secure a somen hat thicker coat.


In the construction n mushroomi houses care should be taken to
make the hiildin:I. as tight as Ph-.'ilhr .Ain 1' with f.v outlets. If
windo- are necessary they -I,,1,ld be 'small and -lui, li e -, ir' ii,
with tine wire i:iii/,. which forms- an excellent prevention :'.linst
lhe entrance of both I i.,IL-.-t- al.nii mites,- a-s 1pr. iI n i, n irI. If
po.-'ildle all compost w-i',ill he steamed 1 nt',i,. .i iWiW placed in ithe
liinise and the lIrilr.ihilre -I,, ill he kept I elow .:* -,' F.. a- all insects
air more or less li, iiii. at this temnIperattre and their otherwise
SSee reprint from Bul. 60, Bur. *:ni, U. S. I'8 l .' Agriulture. pp, :I.-1 l3 i r
Iioxil as an Insecttlcde.


rapid iiiiiltipli(-ation is thereby greatly checked, reducing infestation
to a minimum. If these recommendations are carefully followed
there should be little necessity for the radical measures of fumigation
or destruction of the beds.
Secrebio : of .\ir' ,tuiv.
WASHINGTON, D. C., April 17, 1.912.

ADDITIONA. L COPIES of this publication
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