[Talk-us] Municipal Tree Survey
Jerry Clough - OSM
sk53_osm at yahoo.co.uk
Fri Sep 23 16:06:21 UTC 2016
From: Frederik Ramm <frederik at remote.org>
To: talk-us at openstreetmap.org
Sent: Monday, 19 September 2016, 19:09
Subject: Re: [Talk-us] Municipal Tree Survey
On 09/19/2016 05:13 PM, Adam Old wrote:
> For the most part we would like to send people out using their mobile
> devices and an app like Go
> Map!! https://itunes.apple.com/au/app/go-map!!/id592990211?mt=8
> <https://itunes.apple.com/au/app/go-map%21%21/id592990211?mt=8> or a
> paper survey form that we could then update OSM with. Hopefully this
> would introduce a good number of new people to OSM as mappers and/or
Sounds like a win-win situation.
Frederik Ramm ## eMail frederik at remote.org ## N49°00'09" E008°23'33"
I'd agree with Frederik.
Only this morning I was looking at a site for volunteer tree wardens in Surrey, England; and at the weekend a friend in our party was visiting what are known as veteran trees in Kent.
We already have a fairly extensive set of tags for mapping trees and their attributes. In a few places well-attributed tree data has been imported to OSM: take a look at Vienna of the London Borough of Southwark as examples for a reasonably extended set of tags.
Basically I would look for a minimum of circumference (in UK this is usually Breast-height girth BHG or roughly circumference at 1.5 m above ground level), species (& if appropriate cultivar). Not strictly necessary but very useful are genus (especially if precise species is not known, or for things like flowering cherries), leaf_type & leaf_cycle (both make it easier for data consumers & editors). Date of planting is very useful but often not readily available.
Now to other things:
- Height. Harder to survey if not specifically equipped for the purpose. Obviously useful.
- Spread. Again a bit harder to survey, although finding the drip line on wet days makes it easier. This is less often added to tree data in OSM, but there was an interesting HOT project using tree spread to estimate fire risk. I have the details somewhere.
- Condition. I think as long as volunteers are working from a protocol to assess tree condition there is no trouble in adding it. If you do have a given scale then it may be worth adding the information to the wiki, and then others can use it. It may also be useful to use a condition:description tag to add additional information (e.g., crown thinning, leaf spot, fungal growth etc).
- Survey Date (actually should be tagged last_survey_date). Important for assessing things like height & condition, but also circumference. The professional arboriculturalists woring for my local council seem to get round the tree estate every 3 years: adding or updating tags at his frequency on OSM is unlikely to cause any issues.
- Proposed Work. This is the only item raised which does not fit into OSM typical tagging approach, but I can see no harm in it.
Lastly & most important from a mapping/tagging perspective:
By all means use OSM but create & maintain your own unique identifiers for the trees. OSM identifiers are not guaranteed to be stable, and the nodes may accidentally be re-purposed. Current best practice is for trees to be labelled with a tag giving the identifier for the tree register ( (See this site for examples). Even if a register is only kept in a spreadsheet (which I wouldn't recommend as I've accidentally created duplicates when doing it myself) the identifiers can be added to OSM as ref tags.
For actual mapping of trees either use an enhanced version of an existing OSM tool (e.g., Vespucci can read xml files designed for josm), or combine something more dedicated to capturing tree data with more accurate GPS readings (I use ObsMapp & add Garmin waypoint info when recording species detail). To date I've found using a mobile phone app GPS a little unreliable when mapping trees which are close together, the individual trees are often not positioned correctly in relation to adjacent trees. If you have good quality aerial imagery (or even better Lidar) then use this as the guide. A tape measure or digital measurer, and compass are still useful tools for getting correct relationships within a grove of trees.
Lastly, I'd like to point out that this data is useful for many purposes. As an enthusiastic amateur entomologist I often want to search out rarer trees to see if I can find particular insects. I've written about the possibilities for using city tree registers for education here: From Mapping Trees to Tree Trails: some thoughts
Best wishes with the project.
Coda: I was vaguely aware of OpenTreeMap but they seem to be anything but open with a monthly charge of 80 bucks.
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>From Mapping Trees to Tree Trails: some thoughts
The other day I engaged in a twitter conversation with Oliver Pescott, a biologist at the Centre of Environment ... | |
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Latschbacher Tree Tagging | Richmonds
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