BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Gleditsia triacanthos | Honey-Locust 



GENERAL BOTANICAL CHARACTERISTICS : 
Honey-locust is a native, deciduous tree.  Mature heights usually range
from 49 to 98 feet (15-30 m) [11,36], with a maximum height of 140 feet
(43 m) [14].  In natural stands honey-locust averages 70 to 80 feet
(21-24 m) in height [8].  Honey-locust is armed with heavy branched
thorns on the lower branches and trunk [11].  The crown is plumelike and
open [14,42].  The bole is usually short and often divided near the
ground.  The bark of mature trunks is usually 0.25 to 0.75 inches
(0.6-3.5 cm) thick with narrow ridges divided by fissures.  The bark
peels in strips [14].  The thick, fibrous roots are deep and
wide-spreading [14,39].  The tree is sturdy and windfirm [14].  The
fruit is a legume 8 to 16 inches (15-40 cm) long and 1 to 1.4 inches
(2.5-3.5 cm) wide [8,11,22].

Honey-locust is usually described as rapid-growing [8,39].  Average
longevity for honey-locust is 125 years [8].

Unlike most leguminous species, honey-locust does not form Rhizobium
nodules on its roots, and does not fix nitrogen [12].


RAUNKIAER LIFE FORM : 
   Phanerophyte


REGENERATION PROCESSES : 
The mimimum seed-bearing age of honey-locust is 10 years.  Optimum seed
production occurs from about 25 to 75 years of age.  Seeds are produced
until about age 100.  Large crops usually occur every other year but can
be produced annually.  Some seed is usually produced every year.
Honey-locust seed is viable for long periods due to an impermeable
seedcoat.  Seeds are dispersed by birds and mammals, including cattle.
Germination of honey-locust seeds is apparently enhanced by passage
through the digestive tract of animals.  Germination is artificially
enhanced by scarification (both hot water and acid treatments are
effective) [8].  Honey-locust seeds showed the broadest germination
response of five species tested (honey-locust, white ash [Fraxinus
americana], sycamore [Platanus occidentalis], red mulberry [Morus
rubra], and black cherry [Prunus serotina]).  Honey-locust showed a high
rate of emergence under all temperatures tested, and under all but the
driest conditions.  It was also the only species of the five that had a
higher proportion of variance in germination rate explained by moisture
than by temperature [13].

Honey-locust seedlings grew faster on clay soils than on loess and
alluvium.  There was no growth difference between sun and shade on clay
soils, but on the other two soil types honey-locust seedlings exhibited
retarded growth in the shade.  Seedling root depths were 5 to 5.25 feet
(1.5-1.6 m) on clay and 20 to 24 inches (50.8-61 cm) in moist alluvial
soil [7].

Honey-locust can be propagated by grafting, budding, and cuttings
(hardwood, softwood, and root cuttings) [8].


SITE CHARACTERISTICS : 
Honey-locust is adapted to a variety of soils and climates [14].  It is
common in both bottomlands and uplands, in the open or in open woods
[16].  Honey-locust occurs on well-drained sites, upland woodlands and
borders, old fields, fencerows, river floodplains, hammocks [22], rich,
moist bottomlands [8], and rocky hillsides [36].  It is most commonly
found on moist, fertile soils near streams and lakes [8].  Best growth
occurs in small stream valleys in southern Indiana and Illinois [14].
It has been rated highly tolerant to flooding [24].  It is also
drought-resistant and somewhat tolerant of salinity [37,39].
Honey-locust tolerates both alkaline and acid soils, but its best growth
occurs on soils with pH between 6.0 and 8.0 [8].  Honey-locust grew
better on low nitrogen sites than many other tree species [1].

The natural range of honey-locust is generally below 2,500 feet (760 m)
elevation, although the upper limit appears to be 5,000 feet (1,520 m).
A 20-year-old plantation of honey-locust had good survival at 6,900 feet
(2,100 m) in Colorado, but the trees were small [8,16].


SUCCESSIONAL STATUS : 
Facultative Seral Species

Honey-locust is intolerant of shade.  Reproduction establishes only in
open areas, gaps, and at the edges of woods [8].  The ability of
honey-locust to invade open prairie is thought to be related to its
tolerance of xeric conditions [3].  Both top and root growth are
retarded by shade.  Lower limbs die back in excessive shade.
Honey-locust is a fast-growing member of early seral stands [8].  Hupp
[45] classes honey-locust as an upland disturbance species which is
sometimes found on the most severely degraded stream channels (streams
disturbed by stream channelization projects).  The presence of
honey-locust and similar species suggests that these streambanks are now
so high as to be above most fluvial activity, and that these sites are
highly disturbed [45].  Honey-locust is also described as a
mid-successional species [41] and is found in gaps or on the edges of
old-growth forests [10].  The distribution of honey-locust appears to be
related to the serendipitous combination of openings (disturbance) and
seed dispersal.

In southeastern Iowa, honey-locust was one of the major dominants in
pioneer forests that developed on abandoned fields and pastures [44].
Honey-locust is also a pioneer in the rocky limestone glades of
Tennessee and Kentucky that are later populated by eastern redcedar
(Juniperus virginiana) [8].  In Mississippi, honey-locust was a
volunteer on an 11-year-old hardwood stand planted to Nuttall oak
(Quercus nuttallii).  At 20 feet (8.8 m), it was the tallest tree in the
stand.  It is likely that honey-locust will eventually be overtopped and
shaded out by other species as the stand matures [25].  In Tennessee,
honey-locust was present on a 12-year-old site (oldfield succession),
but not on 3-, 28-, 30-, 40-, and 45-year-old sites [34].

In southeastern Texas, honey-locust was present at very low density on a
47-year-old gravel pit, but was not present in 3- and 5-year-old pits or
in adjacent undisturbed forest [31].  In southwestern Ohio, honey-locust
was common in 50-year-old forests (on old fields), and present but not
common in 90-year-old and old-growth (over 200 years old) forests
[41,41].  In Ohio, honey-locust was an occasional member of the canopy
of 40- and 60-year-old oak (Quercus spp.)-sugar maple (Acer saccharum)
stands [15].

In central Indiana, honey-locust was present in edge plots but not
interior plots in an old-growth forest [10].  In Kansas, honey-locust
grew in patches on the edges of Konza Prairie gallery forests, reaching
heights of up to 20 feet (6 m); under the canopy it was rarely over 6 to
8 feet (1.8-2.4 m) tall [33].  Large honey-locust trees were present in
a mature shingle oak (Quercus imbricaria)- bur oak community in Kansas,
suggesting that they were relics of an earlier successional stage.
There was no honey-locust in the reproduction layer [44].


SEASONAL DEVELOPMENT : 
Honey-locust begins to flower when its leaves are nearly full grown,
from around May 10 in the southern parts of its range to around June 25
in the northern parts of its range [8,42].  The legumes ripen from
September to October, usually falling after ripening but sometimes
remaining on the tree through February [8,16,39,42].

Related categories for Species: Gleditsia triacanthos | Honey-Locust