FIRE EFFECTS
SPECIES: Maianthemum canadense | Wild Lily-Of-The-Valley 



IMMEDIATE FIRE EFFECT ON PLANT : 
Fire top-kills wild lily-of-the-valley.  Surviving rhizomes grow, and
flowers are initiated the first growing season following a fire [27].
Wild lily-of-the-valley flowered in June following low-severity fires
(i.e., surface litter layer was consumed) during October and April.
Flowering began 22 days earlier on the fall-burned than on the
spring-burned plants, and fruit developed on fall-burned but not on the
spring-burned plants [17].  Wild lily-of-the-valley sprouted within 2
weeks after a prescribed fire and was common in all stands; however,
cover had decreased [108].  In stump-prairies of northeastern Wisconsin
that were burned in the spring, it sprouted by summer and increased in
frequency [121].  Seven soil core samples were collected 1 week
following a low- to moderate-severity ground wildfire in April in a
boreal mixed conifer-hardwood forest.  In the soil samples, most wild
lily-of-the-valley developed from surviving rhizomes; however, five
seeds germinated from three of the samples [6].


DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
NO-ENTRY


PLANT RESPONSE TO FIRE : 
Wild lily-of-the-valley recovers slowly after fire [17,70].  Its
recovery rate may be variable due to the severity of burning or to
successive annual fires.  Wild lily-of-the-valley can be one of the
first species reported on a fresh burn [124].  In a boreal mixed wood in
New Brunswick, it had widely variable reponses during different seasons
of burning (spring, summer, or fall); therefore, averaged responses
among seasons was similar [45].  In western Maine following a severe
fire where the organic soil was consumed, surviving wild
lily-of-the-valley sprouted after 1 month [109].  However, it occurred
infrequently 2 years after a severe summer burn in which all the litter
and humus were destroyed and the mineral soil was exposed [82].  In a
jack pine stand in northeastern Minnesota under various silvicultural
and prescribed burning treatments, there was a 20 percent decrease in
wild lily-of-the-valley 1 year following prescribed burning when
temperatures were less than 900 degrees Fahrenheit (482 deg C).  Its
frequency decreased by 70 percent where temperatures mostly exceeded 900
degrees Fahrenheit (482 deg C) [1].  There was a significant (p<0.05)
decrease in wild lily-of-the-valley biomass 2 years after a winter
clearcut and summer prescribed burning in northern Minnesota [94].

Wild lily-of-the-valley took 4 to 10 years to seed in from nearby areas
following prescribed fires on clearcuts seeded with jack pine [18,19].
Soil samples were taken from burned and unburned areas 3 years after a
fire in an old-growth red pine (Pinus resinosa) stand.  Wild
lily-of-the-valley germinated only in soil from the unburned area [4].
It was less frequent in open, burned areas than in unburned areas in
oak-pine woods [13].

Following two successive annual, low-severity fires where the duff was
not consumed, wild lily-of-the-valley remained a dominant species with
increases in relative densities or frequencies at postfire years 1 to 3
[83,86,91,107].  It decreased in frequency from pretreatment levels of
42 percent down to 1 percent following logging with 2 successive years
of prescribed burning [55].  In cutover areas aged 2 to 40 years since
fire, it had only 0 to 2 percent cover [83].  Following prescribed
spring fires in boreal mixed woods, wild lily-of-the-valley frequency
declined from 40 to 16 percent.  Its frequency further declined to 8
percent following another fire 6 years later on this area [79].

Wild lily-of-the-valley had lower frequencies (53 and 57 percent) than
the control (97 percent) 11 and 14 years after fires in mixed
conifer-hardwoods in northeastern Minnesota [70].  It was one of the
most abundant species present 13 years following a severe wildfire in
mixed conifer stand in Minnesota and Ontario [2].  In different burns
aged 9 to 50 years in Ontario, wild lily-of-the-valley had the highest
density on burns aged 25, 29, or 50 years [102,110].  At postfire year
33, it had similar frequencies (25 to 33 percent) and cover (1 to 2
percent) in four different forest communities of aspen-birch, birch,
jackpine-birch, and jack pine [90].  In moist mixed woods in North
Dakota, its relative cover 80 years following fire was not different
from unburned areas [95].  Fuel loadings were variable in fire-prone
forest stands in Michigan where wild lily-of-the-valley was a typical
understory species; it was present in low frequency (0.3 percent) 84
years following fire [79].

There was no significant (p>0.05) difference in the occurrence of wild
lily-of-the-valley under five shade treatments (0 to 100 percent shade)
following a low-severity prescribed spring fire [57].


DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
NO-ENTRY


FIRE MANAGEMENT CONSIDERATIONS : 
Measurements on wild lily-of-the-valley were used to develop regression
equations for predicting changes in forest floor moisture in upland pine
communities [20].  There were no seasonal trends in change of moisture
content for wild lily-of-the-valley during a study to assess understory
flammability in Great Lakes coniferous forests for use in the National
Fire Danger Rating System [78].  Spring burning may be the most
effective control for wild lily-of-the-valley during site preparation
because carbohydrate reserves are lowest, potentially reducing plant
vigor [42].

Related categories for Species: Maianthemum canadense | Wild Lily-Of-The-Valley