Every time you cruise with Plot Hound, you automatically get a bunch of beautiful graphs for free. In this post, we'll walk through how to interpret all of the new graphs.
The basic graph of diameter distributions is similar to the previous version. Graphs now use a more distinctive color palette, and contain both solid and dashed lines depending on how many unique species are present.
Based on your feedback, we know that this basic graph can be difficult to read and interpret when a stand has a large number of unique species present. We’ve added a selection of other graphs to aid in visualization of stand structure, both for individual species and the dominant species in a stand.
There are two faceted graphs showing the distributions of individual species. One is black and white and one is in color; otherwise, they are identical. The color graph uses the same colors for each species as the overall graph, for continuity and so you can compare back-and-forth. The faceted graphs show the distribution of each species separately, without the overlapping that occurs when all are graphed on the same axis.
The example graph here shows that the faceted graph provides additional information about species that is hard to discern from the overall graph. Looking at the overall graph, it’s difficult to see the distributions in the middle and larger diameter classes. The faceted graph shows more easily that, for example, there are similar distributions of hickory and elm species in the middle diameter classes, with the largest number of trees per acre occurring around the 18-inch diameter class. You can also see that water oak shows a similarly-shaped distribution but with the largest number of trees per acre in approximately the 15-inch diameter class.
The next new graph shows only the distributions of the three most dominant species in the stand. Dominance is defined in this case by the three species with the highest basal area. This figure highlights those three species, showing their relative distributions, without being crowded with the additional curves for all the other species in the stand.
The final new graph is simply a breakdown of the species in the stand into broad hardwood and softwood categories. We’re using the USFS Forest Inventory and Analysis definitions for hardwood and softwood for North American species - softwoods are conifers, hardwoods are deciduous. Aspen species are “hardwood”.
You may also notice that there are smooth confidence intervals around the curves, gray in the faceted graphs and colored in the graphs of dominant species and major species group. Those are 90% confidence intervals (we'll explain how to interpret these in the next post). The width of the interval reflects the variability of the species between measured plots. We’ll do a future post showing the connection between plot- and stand-level data and those confidence intervals, to aid in their interpretation.
As before, the graphs reflect English units - trees per acre, and diameter in inches, and as before, please contact us if you are interested in different units or graphs! We’re always interested in hearing what you think about the new graph options, and if there’s anything else you’d like to see.
Tuesday, February 11, 2014
Friday, February 7, 2014
One of our top requests (usually from those of you working in southern pine plantations) has been for a quicker way to add measurements for your most common trees. Today we're rolling out a change that should really speed up your cruising.
You'll also notice that we've also sped up data entry for the "old" screen too. We've focused on making everything feel much snappier so that you can focus more on cruising and less on data entry.
On your "Trees" screen, you'll now see a mini-form for entering a species and diameter. Simply select the species and diameter you'd like, and then hit "Quick add tree" to add that measurement. You can hit the button multiple times to add multiple trees, as shown below.
Posted by Max at 10:17 AM
Saturday, February 1, 2014
At SilviaTerra, we're welcoming in the new year with a total refresh. Our redesign was focused on formatting and presenting your data in a way that makes it easy to understand.
If you've been using the Plot Hound app or website lately, you've probably noticed a clean new look that puts your data front and center. One of the biggest changes we made was improving the quality of the graphs that get generated when a cruise is completed.
We’ve tweaked the diameter distribution graphs that are produced as part of your basic cruise summary. Now you'll see additional graphs that show different views of the data, emphasizing different aspects of the forest composition.
Over the next few weeks we’ll do a series of blog posts talking about those graphs in more detail, highlighting some of the differences among the various new graphs and providing some guidelines for interpreting them.
Posted by Max at 1:34 AM