A Study Of Ctla Formula Values

Gary Watson

doi:10.48044/jauf.2001.032

Article Figures & Data

Tables

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Table 1.

Appraisal data collected and calculations performed.

Required Data
State/ZIP code
Year appraised
Dbh
Species name (uniform species code assigned)
Species rating
Condition rating
Location rating (site, contribution, and placement for the 8th edition of the Guide)
Site class (street, residential property, commercial, parking lot, etc.)
Basic price (value per trunk cross-sectional square inch in U.S. dollars)
Largest commonly available transplanted tree value and size (8th edition only)
Cleanup and repair costs
Settled value
Casualty loss or inventory
Client responsible for or experiencing loss (casualty loss only)
Serial number (assigned)
Guide edition used
Calculations
Location (8th edition)
Trunk cross-sectional area (adjusted for large trees as required by 8th edition)
Formula value without condition rating (varies with edition used)
Appraised value (converted to 1998 dollars, the year for which the most recent Consumer Price Index information was available at the time the database was finalized)

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Table 2.

Comparable appraised values for trees by species class and size class derived from actual formula method appraisals. High and low values represent the mean ± one standard deviation. Values are expressed in U.S. dollars.

Species class (%)	Low value	High value	No. of records	Low value	High value	No. of records	Low value	High value	No. of records
	4-in. dbh			5-in. dbh			6-in. dbh
10	0	94	51	1	103	14	0	142	10
20	35	94	445	58	155	157	82	186	68
30	3	171	554	61	244	310	74	308	147
40	15	198	1,405	85	297	626	88	393	276
50	59	186	1,803	124	320	1,031	135	429	319
60	57	214	1,591	166	324	1,089	176	455	281
70	70	219	3,515	185	335	2,543	210	472	940
80	82	219	2,905	177	358	2,007	217	500	844
90	67	240	1,620	177	357	824	246	490	510
100	101	205	628	204	313	445	296	444	56
	7-in. dbh			8-in. dbh			9-in. dbh
10	^*	^*	^*	^*	^*	^*	34	145	29
20	73	248	142	87	329	50	173	301	157
30	97	405	225	119	482	113	190	538	276
40	173	478	524	181	580	233	247	696	518
50	255	514	779	233	665	298	337	782	920
60	325	533	1,152	327	683	300	434	821	1,087
70	356	560	2,578	402	696	1,009	530	821	3,349
80	348	596	1,896	392	770	1,063	531	878	2,328
90	333	608	751	427	776	499	535	891	950
100	359	549	343	497	722	92	571	832	362
	10-in. dbh			11-in. dbh			12- to 14-in. dbh
10	0	516	11	0	695	11	^*	^*	^*
20	304	384	39	346	528	241	253	446	258
30	Til	653	122	310	837	349	403	834	579
40	314	831	262	404	980	515	476	1,215	708
50	431	902	271	487	1,102	875	645	1,416	735
60	423	1,070	323	589	1,168	1,006	726	1,621	1,122
70	591	1,036	1,316	758	1,133	3,289	972	1,577	3,769
80	650	1,082	1,379	754	1,237	1,922	984	1,682	2,394
90	667	1,143	503	800	1,255	776	1,027	1,672	991
100	770	1,091	76	857	1,228	354	1,041	1,607	509
	15- to 16-in. dbh			17- to 18-in. dbh			19- to 20-in. dbh
10	0	516	11	0	695	11	^*	^*	^*
20	229	689	213	363	895	154	358	1,079	197
30	557	1,006	749	649	1,296	983	837	1,436	981
40	612	1,504	722	657	1,900	842	764	2,261	923
50	829	1,749	557	839	2,253	354	972	2,719	251
60	919	2,029	856	1,094	2,457	681	1,331	2,941	609
70	1,205	2,020	3,121	1,434	2,501	2,656	1,813	2,956	2,591
80	1,235	2,176	1,962	1,445	2,797	1,648	1,794	3,388	1,422
90	1,332	2,173	701	1,655	2,817	577	2,091	3,419	485
100	1,336	2,170	458	1,756	2,872	449	2,159	3,594	407
	21- to 22-in. dbh			23- to 25-in. dbh			26- to 28-in. dbh
10	^*	^*	^*	^*	^*	^*	^*	^*	^*
20	412	1,411	103	628	1,586	113	743	1,901	65
30	994	1,706	958	993	2,209	971	1,263	2,620	846
40	865	2,651	983	1,039	3,102	1,566	1,336	3,733	1,435
50	968	3,302	164	867	4,165	148	1,126	5,077	95
60	1,458	3,504	363	1,659	4,217	382	2,327	4,956	292
70	2,062	3,530	2,046	2,357	4,314	2,349	3,162	5,149	2,503
80	2,087	4,071	1,097	2,399	5,018	1,259	3,170	6,116	1,189
90	2,551	4,112	333	3,055	5,062	437	3,835	6,373	408
100	2,804	4,301	406	3,373	5,395	458	4,350	6,727	536
	29- to 31-in. dbh			32- to 35-in. dbh			36- to 39-in. dbh
10	^*	^*	^*	^*	^*	^*	^*	^*	^*
20	1,254	1,861	41	1,454	2,612	11	893	6,014	10
30	1,406	3,594	373	1,700	4,326	242	2,510	6,318	73
40	1,905	4,832	1,076	2,193	5,710	891	3,236	7,506	404
50	2,193	6,132	74	1,655	8,044	42	4,281	8,368	21
60	3,317	6,451	112	3,375	8,040	105	5,240	9,308	43
70	4,051	7,011	1,249	4,854	8,196	1,328	6,176	10,263	813
80	4,263	7,946	792	5,214	9,389	826	6,621	11,700	552
90	5,156	8,053	298	6,349	9,727	243	8,173	12,024	161
100	5,696	8,365	245	6,951	10,516	260	9,087	12,978	164
	40- to 44-in. dbh			45- to 50-in. dbh
10	^*	^*	^*	^*	^*	^*
20	^*	^*	^*	^*	^*	^*
30	3,198	7,525	32	3,915	7,651	8
40	3,223	9,225	191	3,688	10,895	69
50	4,428	10,059	9	3,181	14,693	6
60	5,939	10,898	50	7,268	14,168	14
70	6,988	12,512	434	7,940	17,333	134
80	7,889	14,584	371	10,241	19,141	134
90	10,455	15,305	111	12,900	20,865	23
100	11,913	17,445	92	15,494	22,926	44

↵*Insufficient data.

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Table 3.
Mean dbh measurement, condition, and location for casualty loss and inventory appraisals.
Casualty loss Inventory
Current value ($) 2,507 3,124^*
Dbh (in.) 13.4 15.5^*
Species (%) 71 61^*
Location (%) 54 69^*
Condition (%) 62 53^*
↵*Significantly different from casualty loss at P < 0.001.
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Table 4.
Comparison of appraised value by client type.
Owner of damaged tree Person causing damage
Current value ($) 2,226 2,948^*
Dbh (in.) 13.5 13.3
Location (%) 51 58^*
Condition (%) 58 67^*
↵*Significantly different from owner of damaged trees at P < 0.001.