Vol. 15â1961 - NorthEastern Weed Science Society
Vol. 15â1961 - NorthEastern Weed Science Society Vol. 15â1961 - NorthEastern Weed Science Society
542. The dissolved oxygen content refleoted in general the seasonal trend of temperature, both in the control and experimental plots. The control was consistently the lowest, ranging from 5.5 ppm on June 8, to a low of 4.0 ppm on July 20, and returning to 7.5 ppm on September 15. Within the experimental plots the same trend was apParent, but the variation ocourred over a wider range. On June 8 a reading of 8.0 ppm was oommon, deoreasing to 4.0-6.0 ppm by July 20, and returning to 8.0 ppm by september 15. There appeared to be no correlation of dissolved oxygen oontent with different concentrations of weedioide in the plots. The pH readings, although reflecting slightly a seasonal change were remarkably constant. In both oontrol and experimental plots the readings usually fell between 7.2-7.6. Only during late July when temperatures were high and 02 ppm low did the pH fall to 7.0 in the control and two of the experimental plots. No correlation of pH with different conoentrations of the weedicide can be established. The plankton identified can be conveniently grouped With the same divisions as in previous years: Myxophyoeaei Chlorophyceae (including desmids and diatoms); Protozoa; Rotifera; Annelida; Crustacea (Copepoda, Cladocera, Ostraooda, and Amphipoda); Insecta (larvae or nymphs of Mayflies, Damselflies, Dragonflies, and Diptera); Gastropoda; and Arachnida (many mites). Again as last year, there were So commonly ocourring species large enough to be identified by the low power of the oompound microscope, and many additional tiny forms. The constant ooourrenoe of the same organisms over and over again was monotonous to identify. Out of the 27 hauls made, three forms, Arcella, Microasterias and Ceratium ocourred every time. Many other forms oocurred 25 out of 27 times. No acourate quantitative studies were attempted beoause of the difficulties of preoise collecting. However, any qualitative seasonal variation was refleoted by control and experimental plots alike. Within the first 2 days following application of the granUles, however, the plankton population of all experimental plots appeared to be "siok ll • While it is very diffioult to desoribe this condition, espeoially since there was no quantitative data as proof, the general description is as follows: In all plots, but especially at concentrations of 2.6 ppm and 3.6 ppm, there was a decrease in the phyto plankters, namely the green filamentous and coccus forms and the blue green filamentous. In the large finger boWls, there were fewer lively active crustacean forms, which were usually very abundant and easily seen. In general, a little of everything survived, but the representation 1n abundanoe was poor. Many plankters from the experimental plots died in the finger bowls after two or three hours, while those in the control survived as usual until the following day. It should be mentioned that
543. during these first few days afterapplioation, undissolved granules were often oolleoted with the plankton, and thus the plankton may have been living in extremely high oonoentrations of 2, 4-D for the hours immediately following their oolleotion. By the eighth day after applioation, a deoided lIimprovementtl was notioed in the plankton samples, and by the next sampling date (unfortunately three weeks) all samples resembled the oontrol. It is possible, therefore, that the presenoe of 2, 4-D granules in relatively high oonoentration does reduce the plankton population at least temporarily. At all times throughout the 1960 season, large aquatio vertebrates such as turtles, frogs, and fish were present and Vigorous in t he treated plots as well as the control. Many schools of small, young fish, (l-l~n) were observed swimming aotively in and about the weeds. The benthio organisms dredged and identified in 1960 were members of the same large groups as in previous years. These 8ro.up~were: Annelida (leeches and oligoohaete worms); Gastropoda (several genera, Amnioola, Helisoma, PhYsa a.nd Valvata.); Peleoypoda (Sphaerlum); Ampl'iipoda ( the oommonscud); Isopoda (Asellus); Insecta (larval stages of Mayfly, Damsel fly, Dragonfly, and Midge). Both oontrol and experimental plots showed a seasonal fluotuation. For example, the number of Mayfly larvae oounted in June and in September was lO/dredge, but in late July this rose to SO/dredge. The number of Valvata trioarinata oounted in June was'2/dredge, Whereas in September the oount was aO/dredge. In no sample did anyone group show any significant ~riation from the seasonal fluctuation exhibited by the contro~.
- Page 492 and 493: 4')2. Literatm-o Cit~: Biolog:$,cal
- Page 494 and 495: 494. SYSt.:Clil ..:ne sp:aying cont
- Page 496 and 497: 496. 0ll'l;ljing, &hluL ..l V,~l"Y
- Page 498 and 499: etween our sprayine=. operatdons an
- Page 500 and 501: 500. loblolly pine existed iii quat
- Page 502 and 503: 502. 'j' " Using results for all ou
- Page 504 and 505: cut over several year. ,b.elozoe.·
- Page 506 and 507: 506. HARJJ.rlOOD CONTROL WITHMIST B
- Page 508 and 509: 508. distance was achieved. All sub
- Page 510 and 511: 510. Hardwood oontrol within the li
- Page 512 and 513: • J ". 512. ~ ., and the weather
- Page 514 and 515: ) ) ) '.. . . hble). EffectbeneBB o
- Page 516 and 517: 516. HERBICIDf;TECHNIQUE.:> ,FORTn-
- Page 518 and 519: 518. The possibility o:rusing contr
- Page 520 and 521: 520 • . However, the capacity of
- Page 522 and 523: 522. This is followed by planting i
- Page 524 and 525: 524. AQJJATICWEEDCONTROLANDRELATEDP
- Page 526 and 527: 526. findings we increased the amou
- Page 528 and 529: 52e. There is a constant reinfectio
- Page 530 and 531: 530. in 1960 the Potamogeton re-app
- Page 532 and 533: 532. PROGRESSREPORT ON THE FIELD TE
- Page 534 and 535: 534. It· was tht.;n necessary to d
- Page 536 and 537: 536. l.qunlin Hcrbici(.l(; pr-ove-d
- Page 538 and 539: ;538. P.EFEP..ENCES 1. ijOSCIlETTI,
- Page 540 and 541: 540. The oontrol plot was ohosen so
- Page 544 and 545: 544. Summary 1. Six experimental pl
- Page 546 and 547: 546. A PRELIMINARYREPORTON THE EFFE
- Page 548 and 549: that either slow chemical hydrolysi
- Page 550 and 551: 550. In July of 1959 funds were mad
- Page 552 and 553: 552. The barge was run at ~ speed o
- Page 554 and 555: 554. areas successfully treated in
- Page 556 and 557: 556. pick~rel spawning suacess but
- Page 558 and 559: Control of the Pondweed. Potamogeto
- Page 560 and 561: 560. THE ABSORPTIONANDMETABOLISMOF
- Page 562 and 563: 562. in controlling weeds in ponds
- Page 564 and 565: CommonName WEEDSCONTROLLED ANDAQUAT
- Page 566 and 567: 566. PROGRESS-R!PORT·ON CONTltOLOF
- Page 568 and 569: 568. Herbicides used for these stud
- Page 570 and 571: 570. StHtARy Invasion of Eurasian v
- Page 572 and 573: AUTHORINDEX(continued) ~ King, -Ken
- Page 574 and 575: S/I/pg.2 Dinitro (DNOSBP) •• 11
- Page 576: S/I/4 SUBJECTINDEX{corrt Lnued ) S/
543.<br />
during these first few days afterapplioation, undissolved granules<br />
were often oolleoted with the plankton, and thus the plankton may<br />
have been living in extremely high oonoentrations of 2, 4-D for<br />
the hours immediately following their oolleotion.<br />
By the eighth day after applioation, a deoided lIimprovementtl<br />
was notioed in the plankton samples, and by the next sampling<br />
date (unfortunately three weeks) all samples resembled the oontrol.<br />
It is possible, therefore, that the presenoe of 2, 4-D<br />
granules in relatively high oonoentration does reduce the plankton<br />
population at least temporarily.<br />
At all times throughout the 1960 season, large aquatio vertebrates<br />
such as turtles, frogs, and fish were present and Vigorous<br />
in t he treated plots as well as the control. Many schools of<br />
small, young fish, (l-l~n) were observed swimming aotively in<br />
and about the weeds.<br />
The benthio organisms dredged and identified in 1960 were<br />
members of the same large groups as in previous years. These<br />
8ro.up~were: Annelida (leeches and oligoohaete worms); Gastropoda<br />
(several genera, Amnioola, Helisoma, PhYsa a.nd Valvata.);<br />
Peleoypoda (Sphaerlum); Ampl'iipoda ( the oommonscud); Isopoda<br />
(Asellus); Insecta (larval stages of Mayfly, Damsel fly, Dragonfly,<br />
and Midge). Both oontrol and experimental plots showed a<br />
seasonal fluotuation. For example, the number of Mayfly larvae<br />
oounted in June and in September was lO/dredge, but in late July<br />
this rose to SO/dredge. The number of Valvata trioarinata<br />
oounted in June was'2/dredge, Whereas in September the oount was<br />
aO/dredge. In no sample did anyone group show any significant<br />
~riation from the seasonal fluctuation exhibited by the contro~.