Alligator weed

My pastures, gardens and orchards have been free of Alligator weed for three years now. The rate of plant discovery has declined steadily since first finding Alligator weed in 2011. Finding Alligator weed spurred me to find out as much as I could about the plant and put into place strict management protocol to get rid of it and the resulting chemicals and restrictions placed on our land.

The implications of Alligator weed spreading further on our farm or into the wider catchment are terrible. I have visited natural environments where this has happened and do not wish this weed on anyone or anyplace bar where it came from.

I did lots of research and alongside my observations and existing knowledge on how plants grow created the below protocol that can be used and shared by anyone.

It is an amazing plant that can spread easily and adapt to various growing conditions. It does not seed in New Zealand so people and the way we manage movement through infested areas are the only way it spreads.  To put an effective poisoning program in place you need to allow the plant to grow. The bigger the plant the easier it is to find and the more poison it can take up.

Alligator weed is a serious threat to waterways, wetlands and pasture. It is classified as an ‘eradication pest plant’ in the Bay of Plenty Region which means that the regional council will undertake and fund direct control of alligator weed. Due to the serious nature of this weed it can take years to eradicate. The ease at which it can spread means alongside the eradication program a strict control protocol must be implemented to stop any spread either within or from affected areas. 

All of this hinges on a strong collaboration between Landowners and Regional council to optimize resources and effectively  control and then eradicate this weed.

Below are some facts about Alligator weed, how this affects eradication and what landowners and council staff can do to manage pasture and control programs effectively. Everyone with alligator weed on their property has a different farming situation so the implementation of these programs will look different from farm to farm.  Some things never change however and the sooner protocols are in place the quicker control and eradication will happen. 

Facts Alligator weed;	How this effects management and control	Pasture management for control.	Control
-is a subtropical plant that grows best in warmer weather.	-from spring to autumn plants grow. -as soil warms it out competes grass. -previously ‘dead’ plants emerge from dormancy. -new plants become established and more visible. -plants on a site will be at different stages of growth. (Spraying one week does not mean all surface growth has gone.) - mid to late summer growth is more vigorous.	-for optimal survey and spray areas left un-grazed or trampled for at least 2.5 weeks prior to search/spray. -identified high risk sites should be fenced and treated as a separate paddock to assist pulse grazing. -high risk sites should always be treated as high risk. (Even after spraying as dormant plants will still be emerging.)	-4 weekly survey and spray from October to May. -all sites (dormant) revisited annually and checked for re-growth. -annual extensive survey beyond existing sites during January. -constant communication with landowners as to plant status and future plans.
-is frost tender and the foliage is killed off after hard winter frosts. Winter soil is often wetter and softer. Grass growth is slower.	-there is still a high transfer risk in winter when it is hidden but a low perceived risk as plants cannot be seen. -moist winter ground is easily pugged which fragments and transfers fragments. - soft soil containing root fragments can be easily and unknowingly transferred. -slow grass growth can lead to a looser turf.	-make sure all users are aware of hidden risks. -preferably graze areas when they are dry. -limit thoroughfare of identified high risk sites by stock and vehicles. -minimize duration of stock by pulse feeding within site so that grasses have a chance to stabilize soil and recover. -identified high risk sites should be fenced to limit thoroughfare and treated as a separate paddock to assist pulse grazing.	-checks made on fencing and grazing rotations. -make sure all landowners, users and visitors are aware of protocols and risks.
-can grow in many different forms according to site and pasture management.	-plants can be very hard to spot in recently and low grazed pastures. Leaves are small and stems spread along ground. -if grazing is hard pushed plants can be grazed right off. These plants will re-grow and are still a transfer risk through roots. -plants can be favored so need a recovery period. -plants growing in longer pastures have bigger leaves and are easier to spot. -larger plants can soak up more poison.	-graze sites for a short period of time (2-3 days) at a time. -leave a minimum pasture cover of 3-5cm. -allow pasture to recover for a minimum of three weeks. Greater growth means greater visibility and better poison uptake.	-4 weekly survey and spray from October to May. -communication prior to visit to optimize growth. -communication after visit to inform landowners of new plants and preferred management before next survey.
-looks similar to many other common pasture weeds	-hard to spot.	-allow a good recovery period so that pasture grasses out compete other weeds and alligator weed is more visible.	-good identifying resources. -communication with landowner on survey/spray regime.
-an aquatic plant	-roots are shallower in wet sites. -wet sites often have flowing water or a higher potential for flowing water. -wet sites are more susceptible to pugging which causes fragmentation.	-limit movement of stock and vehicles through sites. -allow infrequent grazing with controlled movement from site. -identified high risk sites should be fenced and treated as a separate paddock.	-in some situations plants can be dug and then sprayed. -silt fences to trap fragments. -annual downstream surveys. -all downstream land users are informed of risks and given identifying material.
-grow extensive tap roots up to 2 meters long.	-can grow in most soil types. -poisons do not kill off entire root system. -plants can re-grow after 3 years of dormancy.	-it should be assumed that all identified plants either alive and growing or sprayed and presumed dead are active. -limit all  thoroughfare. -pulse graze to allow for easy identification.	-isolated plants should be GPSed and marked for easy future reference.
-plants can re-grow from small fragments.	Transfer can be from hidden fragments; -in soil around cuttings or tree root balls. -caught under vehicles or trailers. - on agricultural machinery. -caught in stock hooves. -pulled out when eaten and possibly carried a short distance. -loose fragments* carried with water. -in manure for compost making. -in drain cleanings. *loose fragments can be created with sharp hooves, pugging, skidding vehicles, sharp tools....	-make sure all users and visitors are aware of hidden risks. -create a ‘safe zone’ for loading stock leaving site. -preferably graze areas when they are dry. -limit thoroughfare of identified high risk sites by stock and vehicles. - identified high risk sites should be fenced to limit thoroughfare and highlight risk.	-make sure all users and visitors are aware of hidden risks, updated on changes in protocol and new plants or areas. -clearly identify all high risk sites and isolated plants.
-have nodes on their roots which stop the flow of poison all of the way down.	- poison only kills off the top layer of roots. -plants re-grow for 3-? years until root reserves are exhausted. -a sprayed area can contain re-growth of other alligator weed plants.	-sprayed areas with ‘dead’ plants must be treated as active sites until notified and after each survey and spray.	-isolated plants should be marked for easy future reference. -identified high risk sites should be fenced until all clear is given. -clear communication with landowners about hidden risks.