08.06.2015 Views

Vol. 16—1962 - NorthEastern Weed Science Society

Vol. 16—1962 - NorthEastern Weed Science Society

Vol. 16—1962 - NorthEastern Weed Science Society

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

452<br />

. '!'he cages-used were tw~toot:~bes constl'llCltMlot. half-lnch mesh<br />

galvaniziQ hardware cloth fastened by hog rings. A hor1znnt&1 parti Hon...<br />

about 8 i~. above the bottom divided the cage into two compartments.<br />

Ropes and buoys marked the pos~t10n of each cage .~. the water.<br />

~ , . '':-•. . ,'., .. ~ J:-, ' '. ,; ';<br />

One'Or two days before herb~¢.de applica-t1on ... c~ cage in the Pot~<br />

tests had 25 oysters and 5 blue crabs placedint. ~ttom compartment~<br />

5 small fish in the upper sect1,Qn. In Dundee Cre.~: lQ.fish (pumpklnsee4, •.<br />

Lepom1sdbbosus) were used.~.e Potomac fish w~ ... mixture of pumpkin,<br />

seeds, whiteperch (Roccus wr4qanus) and yello~Jlerch (Perca naveseMl).<br />

In add1Hon sottshell ~l~s ~ere placed .lP:bread tins 6 inches .:<br />

in depth and fll l·25<br />

~ with bot toui:8011. Corners .Qf•.,8iChtin wer.efasterieci to<br />

ropes lea41ng to a buoy line. '.tb~~e groups of c. were placed beside<br />

each caeeln thtj Maryland PotOlll8.C, tributa.ries..~1al cages and trqs: ,<br />

containing large Bl'nups of each .nlmal were plaoe4,;'fiI,t. the center of one of<br />

the salt water plots treated at )0 Ibs. !EVAto provide animals for resi­<br />

·due tests.<br />

ANIMALMOJl'GAkITIOBSEliVATI01§<br />

All .ca.gecianimals in the '~land Potomac'tii~tar1es were examined'<br />

daily for. the fi.rst sevendays.~ter herblc1dea~t+l~t1on. Dur1ng the<br />

second week they were exam1nedt'fl.ce. Exam1naU~tben were madeat .<br />

apprqximate ten-day1ntervals Ullto the t1me"';he~~es were removedat<br />

the end of five. weeks. In the MaCbodoc,on the t,\t~lnia' side, two e~ ..<br />

inations were madeduring the flrst week, one the second, one the third and<br />

the cages removedat the end of the f1fth.<br />

Ananaerob1C.c:ondition deve10pedin one of ~r~&> lb. treatment .<br />

. plots and hd~scrlbed separat~~1.·; \;lith the abovf e;t~eption, no important<br />

differences were observed .in mortalitiesoftest~lmals amongthe thre~<br />

creeks in the Poto~ac area. Statistical analysls:Qfdata from the siml~$r<br />

plQtsls notwarrarited and the~e plots are groupe!:to,ether in the summary<br />

tha t tollows. '11<br />

'. OYSTERS.Nodead oysters were found in any' of th~ cages. except1~<br />

tn theanaeroblcplot, during tbe.,first two week~, A,few scattered deaths<br />

occurred durlngtbe following thr.eweeks· that ~~~x1mate expected ~or~<br />

tali ty amongsimilar oysters In thIs area. Th.1s'f@'*place both in co,",.:<br />

troIs and In· treatment plots e . ,! .condensed,tabu~~on, of the number of .<br />

oyster deaths is shownin Tabie r. ., ..<br />

~',<br />

.'

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!