The Plants of Glacier

Those of you who have seen my pictures of meadows filled with wildflowers at Glacier will not be surprised to learn that Glacier National Park is home to at least 1,132 species of vascular plants. Vascular plants are those plants which have vessels that conduct water and nutrients throughout the plant.  Of these there are 804 types of perennial herbs, 20 different trees, 93 shrubs and vines, and 88 annuals.  Apart from these 1,132 species of plants there are over 200 types of fungi and 855 species of mosses and lichens.  Among all these there are 30 species that are endemic to the region.  This means that these 30 species are limited in range to the northern Rocky Mountains.

Lichen on a rock at Aster Park on Never Laughs Mountain

Glacier is approximately 33% moist coniferous forest and 16% dry coniferous forest.  The remaining area is 8% dry meadow and prairie, 6% deciduous forest and 5% wet meadow or fen.  This makes for a very wide variety of plant life.

An east side aspen grove in fall. 

There is a world of difference between the east side and the west side of  the Park. The west side is a continuation of the Pacific Northwest with cedar and hemlock forest dominating the landscape to the Continental Divide. Moisture from the Pacific coast condenses as it moves toward the Continental Divide making for an average of 30 inches of precipitation.  During normal years the entire month of June is rain or snow.  While on the east side the average precipitation is 23 inches.  The reason for this is that there is almost constant wind on the east side of the divide.  Along the high ridges of the east side one can see the work of the dry Chinook winds. Below, where it is calmer, one finds aspen groves. Most people are not aware of the fact that the aspen tree grows from a genome the average age of which is 10,000 years.

Hemlocks in Sprague Creek

The mountains on the east side of the park are more barren while those on the west have dense cedar and hemlock forests most of the way up the mountain.  The campgrounds on the west side are heavily shaded. Sprague Creek, where we work, has such a heavy canopy of old-growth cedar and hemlock that it can rain for days and there are places that never get wet. By contrast, the campgrounds on the east side have very short trees and no heavy canopy.

Bear Grass

Glacier Lilly

Purple Aster

Despite the great difference the wildflowers grow in abundance on both sides of the Continental Divide. Among the most common and most loved are the Purple Aster (Symphyotrichum puniceum), Bear Grass (Xerophyllum tenax), and Glacier Lilly (Erythronium grandiflorum).  Bear Grass was used by the native Americans as medicine and as a talc for diper rash. The Glacier Lilly is one of the bear's spring-time favorites.  Pamela is hoping to eventually develop a flower guide to Glacier wildflowers. As a result we have many hundreds of pictures of wildflower in our computer. There are pictures of all the hundreds of flowers indigenous to Glacier as well as some of those which are not. 

Spotted Knapweed

Common Timothy 

Yes, there are plants which are not supposed to be at Glacier. They are called invasive species and about 127 of the 1,132 plants fall into this category.  The reason that these non-native plants are called invasive is that they push out native plants.  In nature everything has a reason. For example, as I have pointed out in other blogs, carnivores eat the herbivores. If they don't the herbivore will over graze which will cause a decrease in the density of plants which leads to a decrease in migratory birds and spoiled water sources. The plants on which the herbivore grazes are a naturally balanced diet with the nutrition the animals need. If the native plants, which match the native herbivores, are pushed out by an invasive species, then you are going to have a decrease in native herbivores which is going to cause a food shortage for the carnivore. Well, you can see how it works. 

Oxeye Daisy

Yellow toadflax

The worst offenders among the invasive species are the Spotted knapweed  (Centaurea maculosa), yellow toadflax  (Linaria vulgaris), Canada thistle  (Cirsium arvense), Oxeye daisy  (Leucanthemum vulgare),  St John's Wort  (Hypericum perforatum), Common Timothy (Phleum pretense)  and Sulfur cinquefoil  (Potentilla recta). These plants may be fine where they are native, but they are not fine in Glacier.  



The wildlife and plants at Glacier start to appear toward the end of May with the greatest display being in July.  The saying goes that at Glacier there are two seasons - July and winter.  This brief growing season is even shorter for the sub-alpine meadows at high altitude where the vegetation, as well as the animals, must survive extreme winds, cold night and occasional snow. In 2014 thirty inches of snow fell in Logan Pass (6,686 ft) on June 23rd.  Despite the tremendous difficulties the wildflowers and plants of Glacier never fail but provide the animals with food and visitors with a breath-taking display of beauty an color.