Selecting FIA data

For initial exploration of the data, we will first get FIA plots from NY. We are downloading data directly from DataMart for most up to date information. A harvest is defined as either a 10 in the TRTCD1 column and/or 25% BA removed per acre.

To clean the data, we are only selecting FIA data that was measured in 2005-2021. Finally, we are selecting plots that:

1. Have accessible forestland
2. Are not reserves
3. Are of private ownership
4. Are single condition class
5. Are greater than or equal to 2000 gross BF per acre (initial)
6. Are of Maple/Beech/Birch or Oak/Hickory forest types

Harvest Likelihoods by forest type

Using the Best Practices formula but with avg time between measurement dates rather than invyr

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\(\color{forestgreen}{\text{For Maple / beech / birch group the harvest likelihood is: 47.01%}}\)

\(\color{forestgreen}{\text{For Oak / hickory group the harvest likelihood is: 25.07%}}\)

Breakdown of FIA plots

This table subsets to sites with initial forest types matching Maple / beech / birch group and Oak / hickory group and also initial gross board foot volume being greater than or equal to 2000.

Map of FIA plots

Make a map of proportion of plots harvested in a Unit

Histograms of Previous BAA across forest types

The dotted red line represents the MSU cap (62.5)

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\(\color{red}{\text{For Maple / beech / birch group, the mean BAAC for all plots is **116.75 sqft/acre** and the mean for harvested plots is **123.85 sqft/acre**.}}\)

\(\color{red}{\text{For Oak / hickory group, the mean BAAC for all plots is **112.92 sqft/acre** and the mean for harvest plots is **123.32 sqft/acre**.}}\)

Histograms of Previous QMD across forest types

The dotted red line represents the MSU cap (7)

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\(\color{red}{\text{For Maple / beech / birch group, the mean QMD for all plots is **10.96in** and the mean for harvested plots is **11.53in**.}}\)

\(\color{red}{\text{For Oak / hickory group, the mean QMD for all plots is **10.79in** and the mean for harvest plots is **10.67in**. }}\)

Change in BAA by forest type

\(\color{red}{\text{For Maple / beech / birch group, the number of clearcut plots (i.e., removed at least 70% BAAC) is **5** and the number of thinned plots is **75**.}}\)

Change in QMD after harvest

Harvest behaviors by change in QMD

Percent TPA removed

The red portions of the histograms represent trees that were removed, whereas the grey portions are the trees left to grow. If the red to grey ratio is consistent across the diameter classes, that suggests a thin throughout. If the red to grey ratio is higher in the higher diameter classes, that suggests a thin from above and if the red to grey ratio is higher in the lower diameter classes, that suggests a thin from below.