Rare Plant Program

Numerical Analysis of this and Previous Editions

(from CNPS Inventory, 6th Edition, 2001)

As the following numerical comparison of the plants in the six Inventory editions demonstrates, the size of California's rare and endangered flora continues to grow (Table 1). The percentages given below indicate the portion of the total native flora in California represented by the plants on a particular list for the different editions. We estimate that the flora as currently described contains 6300 native species, subspecies, and varieties. This is the number of native taxa that are fully described in The Jepson Manual (about 6000), plus the approximate number that receive peripheral mention as minor taxa.

Table 1. Numerical comparison of the SIX CNPS Inventory editions. We have reevaluated percent of flora for past editions based on 6300 native plants in California.

List or Appendix	Taxa	% Flora
1974, 1st Edition
1. Very Rare & Rare and Endangered	704	11.1%
Appendix I-- Rare and Not Endangered	554	8.8%
Appendix II-- Mostly of Limited Distribution	135	2.1%
TOTAL	1393	22.0%
1980, 2nd Edition
1. Presumed Extinct in California	44	0.7%
2. Rare and Endangered	656	10.4%
3. Rare, But Not Endangered	446	7.1%
4. Rare in California, But Not Elsewhere	237	3.8%
TOTAL	1383	22.0%
*1984, 3rd Edition*
1A. Presumed Extinct in California	34	0.5%
1B. Rare or Endangered in California and Elsewhere	604	9.6%
2. R/E in California, More Common Elsewhere	198	3.1%
3. Need More Information	114	1.8%
4. Plants of Limited Distribution	449	7.1%
TOTAL	1399	22.2%
*1988, 4th Edition*
1A. Presumed Extinct in California	39	0.6%
1B. Rare or Endangered in California and Elsewhere	675	10.7%
2. R/E in California, More Common Elsewhere	177	2.8%
3. Need More Information	149	2.4%
4. Plants of Limited Distribution	508	8.1%
TOTAL	1548	24.6%
*1994, 5th Edition (current)*
1A. Presumed Extinct in California	34	0.5%
1B. Rare or Endangered in California and Elsewhere	857	13.6%
2. R/E in California, More Common Elsewhere	272	4.3%
3. Need More Information	47	0.8%
4. Plants of Limited Distribution	532	8.4%
TOTAL	1742	27.6%
*2001, 6th Edition (current)*
1A. Presumed Extinct in California	29	0.4%
1B. Rare or Endangered in California and Elsewhere	1021	16.2%
2. R/E in California, More Common Elsewhere	417	6.6%
3. Need More Information	52	0.8%
4. Plants of Limited Distribution	554	8.8%
TOTAL	2073	32.9%