Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

Seedling Growth of Intermountain Perennial and Weedy Annual Grasses

J. Tulio Arredondo, Thomas A. Jones and Douglas A. Johnson
Journal of Range Management
Vol. 51, No. 5 (Sep., 1998), pp. 584-589
DOI: 10.2307/4003380
Stable URL: http://www.jstor.org/stable/4003380
Page Count: 6
  • Read Online (Free)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Seedling Growth of Intermountain Perennial and Weedy Annual Grasses
Preview not available

Abstract

Squirreltail [Elymus elymoides (Raf.) Swezey] is a native cool-season grass that has been observed to invade rangelands dominated by the weedy annual grasses, cheatgrass (Bromus tectorum L.) and medusahead wildrye [Taeniatherum caput-medusae (L.) Nevski]. Our objective was to determine if growth characteristics could account for this squirreltail trait. We used growth analysis to examine differences in seedling growth and tissue allocation of 5 squirreltail entries, 2 long-lived perennial grasses ('Goldar' bluebunch wheatgrass [Pseudoroegneria spicata (Pursh) A. Löve] and 'Hycrest' crested wheatgrass [Agropyron desertorum (Fisch. ex Link) Schult. X A. cristatum (L.) Gaertn.]), cheatgrass, and medusahead wildrye. We monitored the 9 entries in a greenhouse for mean relative growth rate, net assimilation rate, leaf area ratio, specific leaf area, leaf weight ratio, root relative growth rate, specific root length, root-to-shoot dry-mass ratio, and root length-to-leaf area ratio beginning 10 days after sowing at 9 destructive harvests at 3-day intervals. Cheatgrass had high relative growth rate for both shoot and root. Only medusahead wildrye equalled the shoot relative growth rate of cheatgrass, and only Hycrest equalled its root relative growth rate. Cheatgrass seedlings were larger than squirreltail seedlings by 2 to 3 weeks after emergence. Few differences were detected among perennials and medusahead wildrye. Cheatgrass displayed the highest leaf area ratio and specific leaf area of the 9 entries but was similar to medusahead wildrye and Red Deer River squirreltail for specific root length. Growth characteristics cannot account for squirreltail's observed ability to invade annual grass stands. However, the combination of high specific leaf area and specific root length in squirreltail germplasm, as found in cheatgrass, may enhance squirreltail survival under competition with annual grasses, especially medusahead wildrye. /// Squirreltail [Elymus elymoides (Raf.) Swezey] es una graminea de invierno nativa, la cual se ha reportado que invade pastizales dominados por gramineas anuales indeseables cheatgrass (Bromus tectorum L.) y medusahead wildrye [Taeniatherum caput-medusae (L.) Nevski]. Nuestro objetivo fue determinar si las caracteristicas de crecimiento de squirreltail pudieran estar involucradas en su capacidad de invadir planteles de gramineas anuales. Su uso análisis de crecimiento y distribucion de biomasa para examinar diferencias en crecimiento de plántulas de 5 poblaciones de squirreltail, 2 gramineas perennes de vida larga ('Goldar' bluebunch wheatgrass [Pseudoroegneria spicata (Pursh) A. Löve] y 'Hycrest' crested wheatgrass [Agropyon desertorum (Fisch. ex Link) Schult x A. cristatum (L.) Gaertn.]), cheatgrass y medusahead wildrye. En condiciones de invernadero, registramos en 9 ocaciones a intervalos de 3 dias, la tasa relativa de crecimiento, la tasa neta de asimilación, la relación del área foliar, el área foliar especifica, la relación del peso foliar, la tasa relativa de elongación de raices, la longitud espectifica radical, la relación entre raiz y vástago, y la relación entre longitud radical y area foliar. Cheatgrass mostró la más alta tasa relativa de crecimento en ambos el vástago y la raiz, aunque medusahead wildrye fue similar en la tasa de crecimiento del vástago y Hycrest en la tasa de elongación de raiz. Las plántulas de cheatgrass fueron mayores que las de squirreltail después de 2-3 semanas. Pocas diferencias se observaron entre las gramineas perennes y medusahead wildrye. Cheatgrass mostró la mayor relación de area foliar y area foliar especifica de las 9 poblaciones, aunque medusahead wildrye y Red Deer River squirreltail exhibieron valores de la longitud especifica de raices similares a cheatgrass. Las caracteristicas de crecimiento de squirreltail aparentemente no son parte de las caracteristicas que permiten a esta especie invadir planteles de las gramineas annuales, sin embargo la combinación de una alta area foliar especifica y longitud radical especifica en squirreltail, tal como se observa en cheatgrass, podria incrementar la sobrevivencia de squirreltail en competencia con gramineas anuales, particularmente con medusahead wildrye.

Page Thumbnails

  • Thumbnail: Page 
584
    584
  • Thumbnail: Page 
585
    585
  • Thumbnail: Page 
586
    586
  • Thumbnail: Page 
587
    587
  • Thumbnail: Page 
588
    588
  • Thumbnail: Page 
589
    589