Weed Mapping in Ku-ring-gai Council

Transcription

1 Current methods for mapping weed densities in bushland areas 23 May 2007 Evelyn Baker 1

2 Background Development of bushland weed assessment guidelines Qualitative assessment of the level of weeds in bushland areas Rapid assessment method Classification provides an indication of the level and type of weed invasion Minimises individual interpretations by weed surveyors 23 May 2007 Evelyn Baker 2

3 In-house Development Weed assessment method has been adapted for use with our Infomaster GIS system by Council GIS programmers Allows for direct data entry in the field Minimises double handling of information 23 May 2007 Evelyn Baker 3

4 Procedure Determine the divisions in vegetative structure Estimate the % weed cover in each division Calculate the weed class Indicate the cause where evident Report the weed classification 23 May 2007 Evelyn Baker 4

5 Select weed common or scientific name Select vegetative structure Upper Middle Lower 23 May 2007 Evelyn Baker 5

6 Select weed density (%) for that stratum <10 (1) (2) (3) >60 (4) 23 May 2007 Evelyn Baker 6

7 Indicate the cause where evident Cause Description Criteria s Physical disturbance of soil Weeds established on natural bare soil resulting from physical disturbance f Imported soil fill Weeds established on imported soil fill often containing weed seed and altered nutrient status d Dumped garden refuse Weeds established by dumped garden refuse containing weed seed and/or propagules v r Physical disturbance of vegetation Impacts of stormwater runoff Weeds established by physical disturbance of native vegetation (eg. mowing, trampling, fire) Weeds established in areas of increased soil nutrients or moisture 23 May 2007 Evelyn Baker 7

8 Choose overall density for each layer Calculate overall weed class for that area Division Scale Weighting Factor Weed Class Upper 1 X Middle 3 X Lower 4 X May 2007 Evelyn Baker 8

9 Draw polygon 23 May 2007 Evelyn Baker 9

10 The final product Weed Mapping in 23 May 2007 Evelyn Baker 10

11 Final map showing noxious weeds layer 23 May 2007 Evelyn Baker 11

12 Recent Improvements More detail for prompt weeds Seeding Size of infestation Is the weed on a watercourse 23 May 2007 Evelyn Baker 12

13 Specific weed identified with a symbol and area 23 May 2007 Evelyn Baker 13

14 Pros and cons of use Does not take into account missing strata Can be difficult to judge location without reference points Noxious weeds not pinpointed Addition of GPS would be useful Locked in edit mode until data capture completed 23 May 2007 Evelyn Baker 14

15 Pros and cons of use Single handling of data Choice of visible layers to gauge potential weed locations (easements) Aerial photos Minimisation of interpretation by individual weed surveyors GIS system provides info on specific weeds Ease of comparison between different surveys 23 May 2007 Evelyn Baker 15

16 Future developments Post treatment box (specifically for prompt weeds) Control method Optimum treatment period Chemicals and additives used Responsible officer Last treatment date 23 May 2007 Evelyn Baker 16

17 Future developments Potential rate of spread based on plant attributes including Seed type Dispersal method Location (waterway) Seed survival 23 May 2007 Evelyn Baker 17

18 23 May 2007 Evelyn Baker 18