BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Elymus lanceolatus | Thickspike Wheatgrass 



GENERAL BOTANICAL CHARACTERISTICS : 
Thickspike wheatgrass is a long-lived perennial, cool-season,
drought-tolerant, coarse-leaved grass [36,39].  It is a sod-forming
species with long, branched rhizomes, by which plants spread rapidly.
The erect culms are 16 to 32 inches (40-80 cm) tall.

In rich soils in the more eastern areas of its range, the root depth of
thickspike wheatgrass plants may reach 6.8 to 11.7 feet (2.1-3.6 m).  In
the more arid western portions roots may penetrate to only 4.8 feet (1.5
m) [11].  Although morphologically similar to western wheatgrass
(Pascopyrum smithii), thickspike wheatgrass is more drought resistant,
albeit less productive [29].


RAUNKIAER LIFE FORM : 
   Geophyte


REGENERATION PROCESSES : 
Seeds usually germinate in 21 days under ideal laboratory conditions.
Germination is improved by prechilling (stratification).  Seedling vigor
is fair, which is better than that of western wheatgrass (Pascopyrum
smithii) but not as good as that of desert wheatgrass (A. desertorum)
and intermediate wheatgrass (A. intermedium) [40].

Thickspike wheatgrass regenerates vegetatively through rhizomes, as well
as sexually via wind-dispersed seeds.  Due to its matted root system,
other species have difficulty establishing in thickspike stands.
Thickspike wheatgrass increases in frequency of individual plants and
percent cover in response to grazing [16].


SITE CHARACTERISTICS : 
Thickspike wheatgrass occurs in grasslands and sagebrush deserts on low
dry plains, dry hillsides, exposed flats and ridges, benches, and
well-drained meadows.  Plants rarely form pure stands over any extensive
area, although they can appear to dominate and can form almost pure
stands over a small area [36].

Although thickspike wheatgrass is best adapted to sand, sandy loam, and
loam soils, it is also found on heavy alkaline flats and weakly saline
soils.  This grass grows on well-drained areas where the water table is
3 feet (1 m) or more beneath the surface [40].

Thickspike wheatgrass plants require from 8 to 15 inches (20-38 cm) of
annual precipitation [29].  When growing in areas with more than 20
inches (51 cm) annual precipitation, plants are not long-lived, because
of leaf and stripe rusts [32].

Plants occur over wide elevational ranges.  These vary as follows [14]:

     from 4,800 to 10,000 ft (1,463-3,049 m) in CO
          5,000 to  6,500 ft (1,524-1,982 m) in MT
          3,800 to  8,900 ft (1,159-2,713 m) in WY


SUCCESSIONAL STATUS : 
Thickspike is present in several climax plant communities [27].  It has
the ability to increase in abundance during secondary succession [36].


SEASONAL DEVELOPMENT : 
This cool-season grass produces its best growth in spring.  Thickspike
wheatgrass blooms from May to July.  Flowering dates are as follows
[14]:

State   Earliest date observed   Latest date observed

CO      June                     August
MT      May                      July
ND      July                     August
WY      June                     August

Thickspike wheatgrass plants mature about 3 weeks earlier than those of
western wheatgrass (Pascopyrum smithii).  The summer regrowth of plants
is fair and the fall regrowth is good [40].

Listed below are the average dates that plants reached various
developmental phases on the Snake River Plain, Idaho [9]:

Growth starts              March 1
Flower stalks appear       May 21
Heads fully out            June 16
Flowers in bloom           June 27
Plant drying               July 12
Seeds ripen                July 27
Dissemination starts       August 8
Dissemination over         August 20
Plant dried                August 11

Related categories for Species: Elymus lanceolatus | Thickspike Wheatgrass