1. Introduction
Impatiens are a genus of plants belonging to the family Balsaminaceae. The family Balsaminaceae consists of two genera. One being Impatiens and the other Hydrocera with only one species – Hydrocera triflora. Impatiens is however a large and diverse genus with more than 1000 species of plants. Impatiens are commonly called Balsam, Jewelweed, Snapweed, and Impatiens as well! Okay. Now that you’re acquainted with the family and the genus, let’s talk about the distribution and the diversity of Impatiens of the Western Ghats.
2. Distribution
The genus Impatiens are usually distributed widely throughout the Northern Hemisphere and the tropics. In India, they are distributed throughout the high altitude and rain-fed areas. They are found in abundance in the Himalayas as well as in the Western Ghats. Sir J.D. Hooker would have divided Indian Impatiens into two wide categories like 1. The Himalayan Impatiens and 2. The Western Ghats Impatiens. I would like to approach this genus in the same way as Sir Hooker did because it makes perfect sense!
3. Impatiens of the Himalayas
They are seasonal plants and can be found only during the spring season. It is only during the spring season the conditions are favorable for these plants to grow and bloom. The winters are too cold and dry because most parts of their habitats are covered in snow.
The Impatiens in the Himalayas are all terrestrial herbs and shrubs. They all share a common flower shape with a long and bigger lip, a shorter spur. Another distinguishing character of the Himalayan Balsams is their elongated fruits which are bulged near the apex. Whereas, the Western Ghats Impatiens have shorter fruits which are bulged in the middle. They are found in moist and cooler regions of the Himalayan mountains.
4. Impatiens of the Western Ghats
It is an entirely different story when it comes to the Western Ghats. There is no such harsh winter in the Western Ghats. This does not mean that the Impatiens can survive and grow here throughout the year. Here the monsoons shower the hills for almost 8 to 9 months every year. Then, there is a dry season for 3 to 4 months. Impatiens germinate, grow, mature, flower and fruit happily during the lush monsoon seasons. They disperse their seeds and die off by the end of the monsoon season and when the monsoon starts again in the next June, the seeds germinate and the cycle repeats.
The Impatiens of Western Ghats are very diverse as compared to those of the Himalayas. The flowers come in different shapes, sizes, the leaves are arranged in different ways on the stem and the plant itself shows considerable variations as it grows on every possible habitat here in the Western Ghats. There are Impatiens that call the forest floor the home, the terrestrial, some grow on rocks as lithophytes, some grow on other trees as epiphytes just like orchids. Some species are capable of growing on rocks as well as on trees provided the conditions are right for their survival! Let me walk you through each of the types.
5. Habitat
Based on the habitat, the place they live in, Impatiens of Western Ghats are classified into three groups.
5.1. Terrestrial
These are the Impatiens that grow on the ground, directly in the soil. They too are very much variable in height and habit. Some are small herbs which grow only up to a few inches (Impatiens inconspicua) while some are large shrubs up to several feet (Impatiens maculata, Impatiens fruticosa) in height. The branching can be very simple (Impatiens oppositifolia) to complex (Impatiens cordata). Some plants can be few branched herbs while some can be profusely branched shrubs. While some grow very close to streams (Impatiens elegans, Impatiens tangachee) while others can happily grow in moist forest floors(Impatiens minor, Impatiens coelotropis). Others even grow in open high-elevation grasslands (Impatiens henslowiana, Impatiens munronii)
The arrangement of leaves also differs greatly with different species. Some species have alternate (Impatiens elegans, Impatiens maculata) leaves while some have opposite leaves (Impatiens lawii, Impatiens minor) and even whorled leaves (Impatiens verticillata, Impatiens gardneriana). There is also a great diversity in the flower shapes and sizes.
5.2. Lithophytes
These are the Impatiens that grow on rocks. Usually these are the rocks that are constantly dripping with water from the land above. These water dripping slopes are perfect habitats for rock dwelling Impatiens or rock balsams.
5.3. Epiphytes
Some Impatiens have even adapted themselves to grow on trees like orchids and some ferns do! They use the trees just as a support for growing and cause no harm to the trees they live on. They are found only in areas with abundant rainfall where there is enough moisture to support these water-needing plants on tree trunks and branches!
6. Habit
Based on the habit of the plant, i.e., the appearance of the plant, they are classified into several groups.
6.1. Scapigerous Impatiens
The scapigerous Impatiens are characterized by the presence of “Scape”. A scape is a leafless flowering stalk produced by the plant. It bears only the flowers and no leaves.
Another important character of these scapigerous herbs is the presence of radical leaves. All their leaves arise from a single point. Thus, they only have a few leaves. The scapigerous balsams usually have a small tuber underground and the radical leaves arise from the submerged tuber. They lack a true stem.
Again, there is a great diversity in the shape of leaf, scape, size and shape of flowers within this group! It would be very interesting to see these plants in the wild, in their natural habitat. It will be as if the plants grow out of nothing on bare, vertical, sheer rock surfaces that drip with water from above!
6.2. Epiphytic Impatiens
Epiphytic Impatiens are, without a doubt, the most interesting type of Impatiens I’ve ever seen! They are the most stunning of all types of Impatiens. Epiphytic balsams are usually found high in the trees but are a sight to behold! They have the most beautiful flowers of all types of Impatiens.
The flowers are greatly modified in shape which make them look exotic and unusually beautiful with bright colors. The stems of the epiphytic balsams are thick and swollen which is an adaptation to survive short dry spells while living high in the canopy. The leaves are too somewhat thicker and leathery that helps to store some water.
6.3. Opposite Leafed Impatiens
These Impatiens are terrestrial – growing on the shaded forest floor to growing in open high-alltitude grasslands among grasses and other plants. They have oppositely arranged leaves and somewhat similar flower shapes. However, there are great variations in the habit, size and shape of leaves, color of the flowers, the presence and absence of spur.
6.4. Impatiens with Umbellate inflorescence
The Impatiens having “Umbel” inflorescence are categorized in this group. They can have alternate, opposite or even whorled leaves. There is also a great variation in the habit, the size of plant, flower color, flower shapes, shape of leaves, presence and absence of spur.
6.5. Impatiens with Racemose inflorescence
The Impatiens with “Raceme” inflorescence are placed in this group. The inflorescence is a raceme with elongated peduncles that bear flowers.
7. Flowers
The flowers of Impatiens show great variation in color, shape, size, presence of spur and absence of spur. The epiphytic balsams have greatly modified flowers with unusual colors as found in the other groups of Impatiens.
7.1. Flower color
The commonly found flower color in the genus Impatiens is pink. There is a great variation in pink color in various species which vary from whitish pale pink color to dark purplish pink color. Apart from pink, other colors in which the Impatiens of Western Ghats exist are purple, white, red, maroon, orange and yellow.
Epiphytic Impatiens have violet, maroon, green, yellow, red in their floral parts.
7.2. Flower shape
Impatiens have 5 petals. One anterior petal called the Standard. 4 lateral petals fused in two pairs to form two Wings. One posterior petal modified into a Lip producing a long appendage called Spur.
For convenience and easy understanding, the floral parts are divided into three –
- Standard
- Wings
- Lip and Spur
The variation is seen mainly in the wings and spur. Though, the standard too shows variation to a great extent, it is not very pronounced in appearance as the standard petal is usually very small.
The wings can be one lobed, two lobed or three lobed. They also show great variation in shapes, sizes and colors.
The spur is an important character of Impatiens and shows a huge variation from one species to another. The spur can be slender or stout, long or short, bulged at the end. The end of the spur can be blunt or sharp. The spur can be straight (usually short) or incurved (usually long). The spur also shows variation in being pink colored (Imaptiens gardneriana), white, green (Impatiens dasysperma). It also shows variation with the presence and absence of hairs. Spur can even be absent altogether in some species.
7.3. Flower size
The flower size also varies from species to species. Some species can have very tiny flowers only a few millimeters across (Impatiens goughii, Impatiens omissa) while some can have large flowers which can be up to a few inches across (Impatiens scapiflora, Impatiens grandis)
8. Leaf shapes
The leaf shapes vary from ovate, lanceolate, ovate-lanceolate, cordate, round-shaped. All Impatiens in India have simple leaves except one species Imaptiens chandrasekharanii which has palmately lobed leaves with lobes 7 to 9 lobes.
However, the leaves are arranged in different fashions. They can be altenate, opposite or whorled in various species.
9. Endemism
The Impatiens of Western Ghats are very strictly endemic plants and there are several degrees of endemism in these plants. Firstly, the Impatiens found in the Western Ghats are all endemic to the Western Ghats and found nowhere else in the world.
They are either present throughout the entire western ghats are they are endemic to an area in the Western Ghats. The Western Ghats itself can be divided into three areas as –
- Northern Western Ghats – From southern Gujarat to Maharashtra
- Central Western Ghats – From southern Maharashtra, Goa and Karnataka
- Southern Western Ghats – From southern Karnataka, Kerala and Tamil Nadu
There are several species of Impatiens that are strictly endemic to each of the above-said areas. Some Impatiens found in Northern Western Ghats cannot be found either in Central Western Ghats or in Southern Western Ghats. This applies to every area and the range of endemism becomes stricter as we move south.
The Southern Western Ghats has the most number of Impatiens in the entire Western Ghats. There is even more specific endemism in the Southern Western Ghats. The reason is the presence of Palghat pass which is a natural gap of about 30 kilometers in the elsewhere continuous mountain range. Such a huge natural gap in the mountain range has caused another level of endemism. This restricted many plants to certain localities because some of these ecologically sensitive plants were unable to move past the pass. While this can be one assumption, there is no solid evidence for this endemism. Another reason could be the microclimates that exist in the Western Ghats due to greatly varying elevations.
One has to keep in mind that the Southern Western Ghats have all the highest peaks in the entire Western Ghats. Several peaks here rise from 2400 m to 2695 m. Many hill stations are located here – Ooty (2200 m), Kodaikanal (2100 m), Coonoor (1900 m), Kotagiri (1800 m), Munnar (1500 m). The highest peak in the Western Ghats, Anamudi (2,695 m) is in the Anamalai Hills of Kerala and Doddabetta (2637 m) is in the Nilgiri Hills of Tamil Nadu.
Several species present above the Palghat pass (In the Nilgiris, Silent Valley) are not found in the mountain range that starts south of the pass. After the pass, the Western Ghats rise again with the Nelliyampathy Hills in Kerala and Anamalai Hills in Tamil Nadu and continue up to the Agasthiyamalai Hills in the south.
10. Some Impatiens of the Western Ghats
Following are some of the Impatiens species that I was lucky enough to have witnessed in the wild!
10.1. Impatiens jerdoniae
10.2. Impatiens scapiflora
10.3. Impatiens balsamina var. rosea
10.4. Impatiens balsamina var. balsamina
10.5. Impatiens campanulata
10.6. Impatiens dasysperma
10.7. Impatiens elegans
Read more about Impatiens elegans in this post – https://www.happybotanist.com/impatiens-elegans-the-elegant-balsam/
10.8. Impatiens latifolia
10.9. Impatiens fruticosa
10.10. Impatiens gardneriana
10.11. Impatiens goughii
10.12. Impatiens inconspicua
10.13. Impatiens leschenaultii
10.14. Impatiens maculata
10.15. Impatiens phoenicea
10.16. Impatiens tomentosa
10.17. Impatiens minor
10.18. Impatiens viscosa
11. Conservation Status
Talking about conservation is an absolute necessity when we have to talk about the Impatiens of Western Ghats. One has to understand the nature of these plants in order to understand why conservation is crucial for plants like these.
Impatiens are very sensitive to changes in their environment. They are very specific in terms of growth conditions. They require consistent moisture in the wind. Dry winds are a big no-no to the survival of these plants. They require constant access to water. Most of them grow near or directly on streams. Most of them love growing in shaded places. Any small change to the above said parameters will result in the disappearance of these plants from their habitat.
There is already enough pressure on these plants from climate change, erratic rainfall patterns, monsoons failing altogether at times, etc. Adding to this, humans destroy their habitats bu clearing the forests for plantation and tourism. This places a huge threat on the survival of these plants and their habitat keeps shrinking which makes them very vulnerable. All of the Impatiens present in the Western Ghats are either endangered or critically endangered as their environment is changed by humans for bad.
The survival of these species hangs on a thin thread. A species of Impatiens existing in huge numbers today does not mean they are safe from disappearing. One small change to their environment can wipe out the plants completely from their environment without the possibility of recovering.
Efforts should be made to preserve the forests that we have right now and increase the forest cover so these delicate beauties can not only survive now but also into the future years.
12. Further Reading
- Arrangement of leaves on the stem – https://www.happybotanist.com/arrangement-leaves-stem/
- Compound Leaves – https://www.happybotanist.com/compound-leaves/
