MANAGING THE SPREAD OF INVASIVE ALIEN PLANTS IN INDIA SCOPES AND CONSTRAINTS K.V. Sankaran

1. MANAGING THE SPREAD OF INVASIVE ALIEN PLANTS IN INDIA SCOPES AND CONSTRAINTS K.V. Sankaran Kerala Forest Research Institute Peechi – 680 653, INDIA sankarankv@gmail.com

2. India India, a mega-diverse country with only 2. 4% of the world's land area harbors 7-8 % of all recorded species Of the 34 global biodiversity hotspots, four are present in India - the Himalayas, the Western Ghats, the North-east and the Nicobar Islands. Exceptionally high levels of endemism in the Western Ghats - 39 sites in India have been inscribed on the UNESCO World Heritage List in 2012. Forests in India - 692, 027 Sq. km-21.05 % of the geographical area of the country

3. The diverse physical features and climatic conditions have resulted in a variety of ecosystems such as forests, grasslands, wetlands, desert, coastal and marine ecosystems Desert to snow clad mountains; tropical wet evergreen to dry deciduous to temperate forests. Threats to biodiversity: land use changes, over exploitation of resources, invasion by alien species and climate change. India was one of the first countries to enact a comprehensive Biological Diversity Act in 2002 .

4. Around 18, 000 vascular plants (12% of world flora); 5725 endemic species Estimated number of alien plants – around 2100 (http://www.griis.org/) Of these, over 300 are reported to be invasive. Damages due to IAS to agriculture and forestry in India - $ 91 million (Pimentel et al., 2001) Costs of IAS in Australia - $ 13.6 billion during 2011–2012 (Hoffman & Broadhurst, 2016) World figures- Economic damage – $1.4 trillion Impatiens verticillata Syzygium palghatense

5. Kerala – south- west corner of Peninsular India. Area 38, 800 sq km - palm lined beaches and backwaters – 44 rivers. Large of chunk of natural evergreen forests– biodiversity hotspot (Western Ghats). Thickly populated - 860 people per sq. km. - high literacy rate 3000 mm rainfall/ yr –tropical wet humid climate. A recent survey for invasive plants in the state recorded 82 species - of which 20 are of high risk

6. Major invasive plants in India and options for their management Mikania micrantha– Fast growing perennial climber - native to Central and South America. Widespread in south-west and north-east India Occupies a variety of habitats including natural forests and agricultural areas. Smothers and kills trees and crop plants. Affects life of tribal people in Kerala Control: Physical: Uprooting/ slashing before flowering and fruiting. Largely unsuccessful because of the heavy soil seed bank and quick regrowth Restoration of sites not practiced.

7. Chemical: Glyphosate and diuron useful but repeated applications necessary. Use of herbicides not permitted in forest areas Biocontrol: A rust fungus, Puccinia spegazzinii, was introduced from Trinidad and released. But, the inoculum load was not sufficient enough to sustain infection. The fungus is reported to be efficient in managing mikania in several countries in south-east Asia and the Pacific. Attempts to reintroduce and release the fungus in Indsia have not been successful so far.

8. Lantana camara: vigorous shrub native to central and south America- reported as invasive in 60 countries. Occurs in disturbed natural forests, agricultural areas and vacant lands. Grows as the main understory in natural forests. Control: Physical: Slashing and pulling. Chemical: Post-emergence application or frilling using systemic herbicides. Biological: Over 40 bio-control agents have been tested across the globe. Over 10 in India. None is known to be successful. Introduction of Aceria lantanae (flower gall mite), Ophiomyia camerae (leaf mining fly) and Puccinia lantanae (rust pathogen) suggested.

9. Chromolaena odorata: Fast growing perennial shrub native to tropical America. Aggressive competitor which forms tangled bushes preventing growth of other plants. Invasion in agricultural areas, natural forests, vacant lands. Control- Physical: Uprooting, slashing, controlled burning. Chemical: Use of herbicides at the seedling stage or on re-growth - better used in combination with physical methods. Biological: A leaf feeding moth Pareuchaetes psuedoinsulata and stem gall fly Cecidochaeres connexa are shown to have some effect. Both have been released in India but with limited success.

10. Parthenium hysterophorus Annual herb native to north and south America. Aggressive colonizer in disturbed sites. Occurs in most ecosystems- drought and reduced land cover promotes invasion. Allelopathic- all parts of the plant are allergic to human beings – causes diseases in animals. Control - Physical: Uprooting before flowering and setting of fruits – restoring the sites with native grasses will prevent re-invasion. Chemical: Several herbicides are useful - must be used before flowering. Biological : A leaf feeding beetle Zygogramma bicolorata and a stem galling moth Epiblema strenuana are widely used in many countries. The former is widely used in the north of India – less so in the south.

11. Mimosa diplotricha var. diplotricha Erect shrub or scrambling climber- can form dense thorny thickets. Native to tropical America. Smothers and kills native plants. Invades wastelands, pastures, disturbed forests, agricultural systems etc. Control- Physical: Uprooting, slashing or burning – uprooting is the best option. Chemical: Use of common systemic herbicides such as glyphosate may be useful but efficacy short lived. Biological: A sap feeding bug Heteropsylla spinulosa that reduces seed production was introduced to the Pacific Islands and Australia. It is yet to be introduced in India.

12. Prosopis juliflora Spiny medium- sized tree with short crooked trunk and large crown – native to south and central America. Invades degraded areas, pastures and croplands forming thickets. Common in arid and semi-arid areas. Used for making charcoal in several states in India. Socio-economic issues. Control- Physical: Thinning and pruning of seedlings. Uprooting/winter burning. Chemical: Basal bark application of herbicides Biological: Two seed-feeding beetles have been released in South Africa. Biocontrol not attempted in India.

13. Leucaena leucocephala Small evergreen trees. Native to Mexico and Central America. Widely promoted for forage production and reforestation. Invades disturbed/degraded sites and agricultural areas- forms dense thickets. Control: Physical: Uprooting of saplings. Cutting promotes re-sprouting. Chemical: Cut-surface and basal and stump bark applications are effective. Biological: A bruchid beetle seed predator, Acanthoscelides macrophthalmus, was released in South Africa -Efficacy unknown. Bio-control has not been attempted in India.

14. Acacia mearnsii (black wattle) Small tree of the highland tropics. Native to south and east Australia. Aggressive colonizer which adapts to a wide range of climates. The long-lived seeds (50 yrs) are distributed by birds and animals. A serious threat to the shola forests and natural grassland in India. Control - Physical: Uprooting seedlings - re-sprouting can occur from left over roots. Chemical: Common herbicides including glyphosate is effective on seedlings. Biological: A seed eating weevil (Melanterius maculatus) has been released in South Africa.

15. Robinia pseudoacacia Medium-sized deciduous tree native to south-east United States. Invasion restricted to the state of Jammu and Kashmir and in temperate zones. Introduced for reclaiming land and as an ornamental Invades agricultural areas, natural forests, planted forests and disturbed areas Easily adapts to drought, air pollutants, frost and high light intensities - Shades out native vegetation and averts growth. Control measures are yet to be attempted in India

16. Ailanthus altissima (tree of heaven) Medium-sized deciduous tree native to north-east and central China Characterized by suckering habit and foul odor. Used extensively as an ornamental tree Grows in moist and loamy soils, but is adaptable to a wide range of soil and climatic conditions. Drought-hardy, does not tolerate dense shade and flooding. Control measures not attempted in India as yet.

17. Sapium sebiferum (Chinese tallow tree) Small deciduous tree native to China and Japan Introduced as an ornamental tree, also cultivated for seed oil. Rapid growth, prolific seeding, adaptation to a wide variety of soil conditions, tolerance to drought, high viability of seeds Seed production to the tune of 100-150, 000/per tree- Introduced in India in 1858 (U.P.) Planted in tea gardens in Dehradun and other high altitude areas

18. New invasions Mimosa pigra Native: Tropical America Threat: This shrub has the potential to spread in natural grassland and floodplains, converting them into unproductive scrubland. Occurs in: Agricultural areas, coastland, natural and planted forests Distribution: Australia, Indonesia, Malaysia, Papua New Guinea, Sri Lanka, Thailand, USA, Vietnam

19. Sphagneticola trilobata (Singapore daisy) Origin: Central America Threat: This creeping herb forms a dense ground cover, crowding out or preventing regeneration of other species. Cultivated as an ornamental. Occurs in: Agricultural areas, coastland, natural forests, planted forests, grasslands. Distribution: Asia- Pacific region

20. Concern Protocol for management of none of the invasive plants developed. Cases of successful management have been developed locally and not widely adopted/transmitted across the country. Success stories of invasive plant management in Kerala Senna spectabilis – Senna is an ornamental tree native to tropical America. A recent invader in the forests of Kerala. Spreads like a wildfire to occupy natural moist deciduous forests. Propagation through seeds which are produced in large numbers. Cutting of trees promotes coppice growth.

21. Through carefully planned experiments we proved that uprooting of saplings and debarking of trees extending below the collar region can control the population of Senna.

22. Salvinia molesta: An aquatic weed, native to south America. Was widespread in the backwaters and rivers of Kerala. A weevil viz., Cyrtobagous salviniae, which burrows through rhizomes of salvinia and feeds on new buds, was released in Kerala in 1983. It had a significant impact on the plant and the population of the weed is now under control. No solution for the widespread Eichhornia crassipes as yet.

23. Management of invasive alien species in India – Scopes 1. The country forms an ideal model system with its diverse mosaic of socio-ecological landscapes. Hence, any success in management of invasive plants will have regional as well as global implications. 2. Commendable expertise in the taxonomy of plants and other species 3. Several Research Institutions/ Universities are working on the ecology and management of IAS – it should be possible to link these institutions and work together to achieve common goals 4. Availability of a comprehensive database on invasive species in the country.

24. 5. Linkages between different Govt. Departments possible so as to prioritize and assign responsibilities 6. Growing attention on the need to conserve biodiversity highlighted the issue of invasive species. 7. The country can benefit from pro-active early response and rapid action system since attempts at management can be very high at this juncture. 8. The economic costs due to IAS in India are huge. This has a direct bearing on the livelihood of people dependent on provision of ecosystem goods and services from natural ecosystems. Management of IAS will help achieve sustainable development goals - a green investment!

25. Constraints • Lack of awareness • Awareness on damages due to IAS needs to be enhanced among policy makers, foresters, agriculturists, NGO’s and the general public • Lack of policy • There is no exclusive national policy or legislation to address the problem of IAS in India. • A multi-agency and multi-programme approach, involving several agencies, is being followed to deal with IAS -this has not been helpful • There are a number of good legislations • The Plant Quarantine (Regulation of Import into India) Order, 2003; Indian Biological Diversity Act, 2002; Environment (Protection) Act (EPA), 1986; Agriculture Pests and Diseases Act, 1914 (and amendments). • But, there are no co-ordinated approaches to deal with the IAS issues.

26. No single agency exclusively devoted to addres IAS issues • The Ministry of Environment, Forests and Climate Change (MoEFCC) deals with matters relating to biodiversity; The Ministry of Commerce and Industry in cooperation with the Ministry of Agriculture and Farmers Welfare deals with implementation of the phytosanitary aspects and quarantine regulations • Lack of institutional mechanism • There are no clear guidelines on how to deal with an IAS problem when identified – who will do what? Who will be responsible for surveys, management/of plants, animals? • Interaction between scientists and policy makers inadequate. • Despite credible scientific proof for the damages that IAS can cause, the issue is yet to find a place in the environmental agenda.

27. Lack of adequate tools, skills and experience in tackling IAS • Regular forest surveillance and early detection and rapid response are seldom practiced. • Lacks quantitative/qualitative information on invasion and spread of alien species. No information on pathways of invasion. • The ecology of many species is unknown which prevents prediction of their impact. This also frustrates attempts at management. • Quarantine regulations need refinement • Capacity building necessary for customs and quarantine officials. Checking at air ports to curb transport of plants, seeds, fruits, etc. needs to be made more rigorous. • Rigorous checking for IAS also needed at sea ports. Domestic quarantine (for all species) at state borders needs to be imposed.

28. Current threats of invasion to India Brontispa longissima (Coconut leaf beetle) Origin: Indonesia and Papua New Guinea Threat: The beetle attacks the youngest spear leaf of coconut. The larvae chew on large areas of the surface of the leaflets and cause death of underlying tissue. As the leaf emerges , the leaflets curl and turn brown, with scorched and ragged appearance.Photosynthesis reduced,. The beetle does not attack leaves that emerge undamaged. Occurs in: coconut palm, Royal palm, Alexandra palm and areca nut palm Distribution: Australia, Malaysia, Cambodia, Lao People's Democratic Republic, Thailand, Vietnam, Maldives, China, Myanmar, Philippines

30. Puccinia psidii( Eucalyptus rust) Origin: South and Central America and the Caribbean Threat: The fungus attacks foliage, inflorescences and young, succulent twigs of myrataceous hosts. The initial symptom is tiny circular yellowish powdery eruptions on the leaf or stem surface which become necrotic and spread on entire leaf, shoot and fruits resulting in die-back. Occurs in: Eucalyptus plantations, guava, syzygium and Pimento plants Distribution: USA, Australia, Japan

31. Main threats to other neighboring countries Bhutan Myanmar Prosopis juliflora Acacia mearnsii Mimosa pigra Robinia psuedoacacia Acacia auriculiformis Ailanthus altissima Acacia mearnsii Sphagneticola trilobata Ailanthus altissima Sapium sebiferum Sapium sebiferum Merremia peltata Broussonetia papyrifolia Miconia calvescens Senna spectabilis Senna spectabilis Sphagneticola trilobata Broussonetia papyrifolia Spathodea campanulata Spathodea campanulata Ageratum haustonianum Ageratum haustonianum

32. Threats to Nepal from across the border (mainly Indian states) Senna spectabilis Sphagneticola trilobata Casuarina equisetifolia Opuntia stricta Spathodea campanulata Merremia peltata Sida acuta Ulex europaeus Pueraria montana var. lobata Prosopis juliflora Clidemia hirta Mimosa diplotricha var. diplotricha Psidium cattleianum Robinia poseudoacacia Ailanthus altissima Ardisia elliptica Sapium sebiferum Tamarix ramosissima Broussonetia papyrifolia Mimosa pigra Acacia mearnsii

33. Main threats to Maldives Chromolaena odorata Mikania micrantha Parthenium hysterophorus Mimosa diplotricha var. diplotricha Mimosa pigra Ageratum conyzoides Imperata cylindrica Senna tora Hyptis suaveolens Clidemia hirta …… the list is incomplete

34. The way forward • Develop a national strategy to deal with IAS in India and establish a nodal agency to implement policies. The agency may: • Develop an unified national system for regulation of introduction of all alien species • Strengthen the national and domestic quarantine measures and ensure proper implementation. Promote inter-departmental linkages to achieve this. • Arrange to conduct forest surveillance for IAS on a regular basis. Ensure adoption of early detection and rapid response (EDRR) to manage recent and future introductions

35. Build capacity of all those who are involved in IAS management. • Implement restoration of degraded ecosystems and areas cleared of alien plants using fast growing native species • Raise awareness on the damages due to IAS among all stakeholders and establish linkages between policy makers, scientists, foresters and others to manage the spread of IAS. • Workout management protocols for the main IAS in India involving scientists, foresters and the local people. Translate the protocols across the country for efficient management of the problem

36. Thanks