1. Email. sederec@gmail.com
SERENGETI DEVELOPMENT, RESEARCH AND ENVIRONMENTAL CONSERVATION CENTRE (SEDEREC)
THE THREAT OF INVASIVE ALIEN PLANTS TO FOOD SECURITY AND ENVIRONMENTAL CONSERVATION IN MARA RIVER BASIN ECOSYSTEM, MARA, TANZANIA
Presenter:
Damian Thobias Magori
Executive Director,
(SEDEREC)
Box 176, Mugumu/Serengeti,
Mara, Tanzania. .

2. KEY AREAS EMERGING ISSUE BEST PRACTICES AND IMPACTS OF C. ODORATA
THE LESSON LEARNED
CHALLENGES

3. EMERGING ISSUE
Invasive Alien Plant (Chromolaena odorata) within Mara River Basin in Mara, Tanzania
C. odorata is a threat to food security and environmental conservation. For the first time it was found in some villages adjacent to Mara river basin in 2011.
It infests crop fields and grazing land leading to a decline in crop production and shortage of fodder for livestock.
It is a fast maturing weed which survives under low moisture conditions and produces many seeds (up to 25,000) that can remain dormant for 3-5 years.  

4. EMERGING ISSUE (…) Chromolaena odorata ( Cont..)
Chromolaena odorata infestation on grazing land within Mara River Basin

5. EMERGING ISSUE (…) Problems caused by C. odorata
Land degradation and water resources are presented in terms of quality and quantity caused by nutrient loss through:
erosion
overgrazing
encroachment into riparian land
deforestation
siltation and
water pollution

6. EMERGING ISSUE (…) C. odorata status in Mara River Basin.
Most affected areas are the Masurura swamp, Somoche and Tobora sub-catchments.
The most affected areas within the Mara River basin

7. BEST PRACTICES AND IMPACTS OF C. ODORATA
The invasive weed has high threat on ecosystem function, biodiversity, water resources, pasture, crop production and human health. It dispersal depends on man, livestock, wind and water.
Characteristics and Impacts of C. odorata.
causes severe pasture production reduction by ≥150 %, thus turning it into a “green desert”;
Produce over one million seeds in a year;
Can completely smother the crop;
It replaces the natural secondary succession and becomes the dominant fallow species ; and
Acts as a host for insect pests that feed on leaves, flowers and fruits.

8. BEST PRACTICES AND IMPACTS OF C. ODORATA (cont…)
Characteristics and Impacts of C. odorata.
C. odorata completely smothering the Banana crop in Mara Basin, Tanzania.

9. LESSONS LEARNED Control measures and uses were lessons learned.
(A) Amongst control measures in practice include:
 Mechanical control – Physical removal by hand, tools or machine
Chemicals control – Applying Herbicides
Biological control - use of populations of upper level organism to suppress pest populations.
Habitat management - e.g. prescribed burning, grazing and changing of the human behavior.
Hunting of prescribed invasive alien species - This is physical finding of individual plants, cutting off woody weeds and applying an herbicide to the cut stem.

10. LESSONS LEARNED (…) Control measures in practice (Cont….)
Integrated control -Use of combination approaches
Containment - Restrict an invasive species to a limited geographical range.
Control - The suppression of a population to an acceptable extent will reduce its competitiveness.
Mitigation - The last option is to “live with” this species in the best achievable way
Cultural Control – Day to day management by communities in their fields. Slashing C. odorata stems manually or mechanically and dug out the roots at least twice during the growing season.

11. THE LESSON LEARNED (…) (B) USES Green manure or fallow component.
Observed to suppress another invasive species which has much worse impacts on agriculture.
Used as a valuable organic soil amendment.
Improved yolk colour up to 5% for egg-laying chickens
Used by traditional practitioners for treatment of burns, wound healing, skin infections, post-natal wounds, and as an anti-malarial; and
Several medical studies have confirmed that leaf extracts have certain anti-microbial, anti-inflammatory and wound-healing effects, and are identified as a potential source of human medicines (Nurul Huda et al., 2004).

12. CHALLENGES The plants coppice profusely from the roots.
An on-going debate to use biological control agents may have adverse effects on non - targeted organisms.
It is not easy to control the weed due to its nature of fast growing , maturing and survival following its inactiveness ;
Cannot effectively be browsed by animals.
Shifting from original place to another increases pressure to new habitats.
Eradication need appropriate program within longtime.
Its expensive to eradicate the weed to a large area of infestation and thus unsuitable for eradication program.
Different national land policies.

13. Thank you for listening
END OF PRESENTATION
Thank you for listening