Day 7: Tree Health Monitor

This post was a bit of a cheat.  I ran out of steam for the 7 Days 7 Gadgets series and only posted this on the last day:

DRAFT
Device to measure tree health through bark, ultrasound, laser on leaf and online supplement of leaf down coloration.  Alerts users to fertilize or water trees.

I'm updating now (2014-12-27) with some more thoughts and information, in other words, a complete post.

Genesis of Idea

In suburban America, one of the most important aspects of your property is the trees on that property.  However, as trees grow, numerous negative things can happen to them that make them dangerous or otherwise problematic to have on your property.  Controlling them, by getting somebody to come in and cut them down, is expensive and a giant hassle.  But, trees are beautiful and worth some measure of investment and time.  So, it would be great if people had better tools to monitor the health of their trees and make good choices about fertilizing and watering those trees.

Details

Prior to engaging in any sensing devices, the user of the TreeHealth system would first download and run the TreeHealth app.  The first step is to create a catalog of all of the trees on the property.  Ideally, the user would do this by walking around the property and pressing a button when they are standing next to a unique tree.  Using the GPS coordinates of the phone, the app would map out all of the trees.  If desired, the user could upload a view of their property's plat and walk to the four corners (for calibration) and map the trees on the property relative to the house.  Without knowing of any better means, the tree's height would have to be estimated.  A digital tape measure (like those used for measuring waist size) should be used for trunk circumference measurements (at ~6" off of the ground).  If the owner knew, they could enter the genus and species of the tree.  If they did not, they could use the app and identify it based on tree characteristics (like leaves and bark).  This should provide a first level view of the tree community on the owner's property.

In addition, the owner would be prompted to enter when the tree looks to be budding and the state of the tree shedding its leaves in the fall.  The dates (compared to the overall tree community in the owner's geographical area) could be another indicator of health.

The Gadget

The TreeHealth gadget would be a multi-sensor device that attaches to a phone (or better, a tablet) that can do the following:

• Measure leaf health via infrared sensors: owner would scan six leaves (enough for a valid sampling without harming the tree?).  My (admittedly weak) understanding is that this is useful for gauging overall health. 
• For larger trees, the owner would use something like a 3/8 hole saw blade to cut a shallow round hole through the bark, then place the ultrasonic sensor on that location.  This could measure the integrity of the tree's main trunk and identify any problems with internal rot and overall fluid/sap flow within the tree.  After the measurements, the owner would glue a special plug in the hole, designed to ensure that the tree was not damaged by the test (or by allowing a fungus or something else bad to get into the tree's systems).

Additional App Features

• Leave measurement: place six leaves on a 1x1" lined mat and take pictures of the leaves.  The meta data of the date will be helpful in keeping track.
• Height estimates: put an object of a known size next to the tree and snap a picture from a known distance away from the tree.  Verify it makes sense by using trunk circumference information.
• CO2 tracking: tell the user how much CO2 was sequestered in their yard.  I'm sure that this will make somebody feel good.  Additionally, if there is a known relation to house height and location, the app could estimate electricity saved from cooling during the summer.
• Fertilization and watering reminders.  Based on geographic weather data, alert user if trees should be getting water stressed.  Suggest watering strategies that will maximized absorption and minimize run-off.

I think that the largest value of this approach is in the continuous monitoring from year to year of the trees.  They don't grown super quickly, so we should have to worry about long term engagement from the user.  Not sure how to do this, but it's probably worthwhile to a local landscaping shop that could be selling to the user year after year.