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The following document is an extract from the Communiqué of the Typha Roundtable Organised by the DFID-JWL project in Hadejia, on Tuesday 17 June, 2003. It explores the nature, occurrence and various methods of control of typha grass – and their suitability or otherwise. It also highlights the measures that the project and its stakeholders are promoting for controlling the spread of the weed in the Hadejia-Nguru Wetlands.

Preamble

Typha spp or ‘cattail’ grass is a species of water loving plant that can, under favourable conditions (i.e. in shallow permanently inundated areas), proliferate and become difficult to control, making the plant an invasive species. Under such conditions it out-competes almost all other plants. In the Hadejia-Nguru Wetlands in particular, and other parts of the Hadejia-Jama’are-Komadugu-Yobe Basin (HJKYB) in general, the invasion by Typha spp or Kachala (in Hausa) has, for the past seven years or so, constituted one of the most alarming threats to the ecology and economy of the area. In recent years, river channels, lakes and fadamas in the wetlands have been taken over by Typha, along with many hectares of farmland and potential grazing lands. On the Marma Channel and Nguru Lake for example, where Typha invasion is more severe, over two thirds of potential farming and grazing lands have been taken over by the plant. Conversely, it has also contributed to the desiccation of the Burum Gana channel, where about 60% of dry season irrigation farms are wasting. In addition, the grass provides a harbour for large flocks of quelea birds that seasonally destroy cereal crops.

This problem of Typha invasion has over the years become a serious concern to the local communities and to traditional authorities, government institutions and line agencies with a responsibility for enhancing the livelihoods of people living in the affected areas. Repeated efforts, ecological studies and manual clearing have yielded very little results in the past.

It is in the light of this escalating problem, growing concern of line agencies and urgent need to find a lasting solution to the menace of Typha, that the State Ministries of Agriculture, Environment, Water Resources, ADP’s and EPA’s in Bauchi, Jigawa and Yobe States have requested the DFID-JWL Project to assist them in their efforts to control Typha grass in the Hadejia-Nguru Wetlands in particular and in the Komadugu-Yobe Basin in general.

As a first step in the search for a solution to the problem of Typha invasion, a ‘Roundtable on Typha Invasion and Possible Control Measures’ was organized to bring together at least 20 representatives of the line institutions and agencies concerned, with national & international experts and staff of DFID-JWL project, on Tuesday 17th June 2003 in Hadejia.

The objective of the roundtable was to enable resources users, decision makers and experts to chart a course for controlling the menace of Typha invasion in the KYB, based on a shared understanding of its causes, impacts, characteristics, the scope of the challenge, experiences in controlling it, and intervention options available.

Discussions

The participants brainstormed and arrived at a common understanding of the following:

Regarding the origin, distribution and types of Typha

From records in the Flora of West Tropical Africa (Hutchison and Dalzul, 1952 – 1972), Typha is probably not an exotic species to Nigeria.

It is found from Lagos to Lake Chad, and from Calabar to Sokoto River Basin

There is probably only one specie found in Nigeria: Typha australis or domigensis

Typha australis is found throughout West Africa, African continent and all other tropical and sub tropical parts of the world.

The Typha genus is found on every continent with the exception of Antarctica.

Regarding its characteristics and impacts:

It reproduces sexually (through seeds) for large area of colonization.

It also reproduces asexually (through the rhyzome) for denser coverage within the immediate area.

It takes oxygen into its roots and new shoots from above the water level through the leaves (fresh air into new leaves/expired air out of old leaves)

General hydrological impacts include: blockage of river channels, which reduces and diverts river flow, increases siltation and over flooding of farmlands and settlements; invasion of flood land farms, extends river banks with the river reducing width of channels

Other general impacts include: provision of habitat for fresh water snails and mosquitoes, etc, which leads to increases in diseases like bilharzias (humans) and liver fluke (livestock) and malaria; crop damage from birds.

Impacts specific to the wetlands include quelea birds infestation; potash intrusion; out migration of local communities; and increased water loss through evapo-transpiration (3 X higher)

Regarding utilisation/harvesting:

To date, no economically/ecologically viable use of typha has been found: the implications of utilisation/harvesting are mostly negative in terms of local socio-economy, hydrology and ecology. This method of control accepts/promotes the negative causes and impacts (outlined above) of typha invasion, compounding the problem of poor water management, and can encourage dispersal of the plant. In areas where typha invasion is severe, such a method is considered highly insensitive and inappropriate to the needs of the local population.

Regarding biological and chemical control:

Biological control: the only known biological control (i.e. Chinese carp – a species of fish that grazes Typha) is ineffective

Chemical control: no herbicide exists that is specific to Typha; therefore large scale control of Typha is NOT RECOMMENDED, but localized small scale control with 2,4 D and Round-up to kill the root system in drained and dry conditions may yield some results.

Regarding physical control:

Using fire encourages vegetative re-growth while standing in water; it can be effective if repeated and there is intensive burning of stem and roots after drainage of water (i.e. on dry soil); burning of the roots is the most critical step.

Hand cutting: again, encourages vegetative re-growth if cut above the water level; when cutting under water level, critical time to cut is when Typha is at the flowering stage, i.e. before dispersing seeds and when the root system has least energy available for re-growth.

Shading, through planting trees along cleared areas or covering up irrigation channels: prevents re-growth as Typha needs high light intensities to germinate. Method suitable for irrigation channels and alongside shores.

Regarding mechanical control:

Use of mowing boats: very expensive, very slow and needs to be repeated continuously (only efficient for large scale irrigation canal management)

Use of floating excavator: has limitations of where it can float and needs side by side accessories for packing debris

Use of suction dredger: again, very expensive, very slow and only suitable for dredging large scale irrigation canals

Regarding water level management:

Short term measures: mechanical/physical Typha control is recommended in conjunction with water level management in both the short term and the long term; draining of large scale irrigation channels (where water levels can be controlled) and burning/cutting of Typha when dry, and sensitizing riparian communities against use of incorrect control methods (i.e. burning or cutting above the water level) that propagate Typha; sensitizing people on the effect of shading and raising community awareness on health/diseases impacts of Typha and on local action they can take, are all envisaged to be promising.

Long term measures: again, water management upstream, in conjunction with draining, burning and cutting and at least one meter deep re-flooding of Typha infected areas (repeated 2 – 3 years), was agreed to hold promises.

Participants Noted the Following

Regarding technical options:

Specific to the hydrology of the KY Basin and the HN wetlands, integration of mechanical/physical control of Typha with water management generally, needs to be tackled in stages.

Stage 1: Priority needs to be given to opening up of the existing water channels in the wetlands to increase flow rates and reduce unwanted flooding.

Stage 2: Structural changes are required in the river system in the form of control mechanisms to distribute water more evenly along different channels (naturally by river training).

Stage 3: Management of dam releases integrated into mechanical control of Typha through dyke building, drainage, burning and cutting and re-flooding.

Regarding institutional options:

The process of getting funds released to attempt the above stages

Option 1: Through high level meeting of Permanent Secretaries and Commissioners in each of the concerned states, to come up with a single memo to present to the Governors of each state to take collectively or through a single Governor to the Presidency. (i.e. following ‘due process’).

The problems identified with this option are that it is too slow, requires so many stages of due process and rarely yields results because of lack of consistent follow up and right pressure in the right places at every stage.

Option 2: Through the Typha Task Force of the concerned states already formed, taking the issue to the Emirate Councils of the concerned states, for the Emirs collectively to take the matter to the attention of the presidency to seek for "special funds" for avoiding ecological crises.

The problem with this option is that, this year release of the ecological fund has been suspended, although other such special funds are being released

Sequel to the above, participants agreed that:

The challenge posed by Typha is too overwhelming for communities, individual LGAs and state governments to control.

There is a need for concerted action with the Federal government in the lead along the lines spelt out above in order for the menace of typha to be brought under control.

Recommendations and Way Forward

The following were agreed upon as recommendations and steps to be taken to move forward:

Regarding short term institutional measures:

Sensitize relevant authority on the issue of controlling Typha.

Identify and take relevant institution on board for immediate action.

Submit proposals to relevant institutions.

Provide relief materials to victims.

Regarding long term institutional measures:

Persuading affected states to make special budget provision through ‘due process’.

Generate funds through the presidency special funds.

Enforce laws (review existing laws) on water management.

Awareness-raising on water management laws among stakeholders.

Adopting integrated water management planning/coordination.

Bringing together all stakeholders to act collectively.

Regarding short term technical control measures:

Chemical applications, cutting/burning regularly especially of shallow areas.

Dredging; opening up of blocked river channel and also, opening up of new channels.

Dyke construction and periodic drainage.

Regarding long term technical control measures:

Erection of dykes and other control or diversion structures.

Ecological audit of whole wetlands.

Large scale integrated Typha control.

Comprehensive river training and dredging/drainage programme implementation.

Conduct research into the nutrient needs, other properties and origin of Typha, with the outlook of using the findings to develop technical control measures.

Immediate actions:

The following were agreed as immediate actions to be taken by institutions represented at the round Table to take the process forward:

DFID- JWL to give support to Typha Task Force for developing short term and long term solutions.

PS MANR Jigawa to call meeting of all line PSs from riparian states before the end of July to enable them to formulate a single memo with a view to presenting it to the presidency.

The Jigawa State Task Force on Typha and DFID JWL Project is to provide support to the Hadejia Emirate Council for the preparation of another memo on Typha to the presidency, as per an earlier agreement between HE, Mr President and HRH, the Emir of Hadejia, which should be complimentary to the one prepared by the PSs.