Nguyen arborist report.pdfNguyen mitigation plan
wvvw rb or 9'Sts n W, co n' I
P.O. Box 909
Mercer Island, WA 980140
(206) 779-2579
What follows is a description of a mitigation plan and discussion for parcel 00513105900606.
The subject property is covered in Red aider trees (Alnus rubra), blackberries vines and two other trees
one Pacific Wfflow and one English Hawthorne. All of the Red Alders have been topped at
approximately 15-20'. The VVMow and Hawthorne are untouched other than being smothered by
blackberries vines. All the, debris frorn the topping was CLA And now Nes flat forrn4ig a mat. The topping
and cutting LIP of the debris flattened a large portion of the invading blackberry . During my first
inspection of the site sprouting blackberries were rmted- it is my professional opinion if left alone within
the next few mon'ths the blackberries wffl re-stabhsh their dominance of the Under story on this parcel. I
revisited the site on 4/3/15 the Wackberries are indeed re -growing and the remaining branches (50%, of
ori&ai crown) on all of the Topped alder's are sprouting leaves. From my observations the trees that
were topped were all hea[thy Red Aider Specimens. Area A on the attached site rnap is and was prior to
fl"ie CUtflng a bare piece of ground next to and under the clti.es side%mA and looks to belong to the city
as found on the COLUIty paircel Vevter. Note the area north of tree,#15 is cornpletelV covered in
biackberry.
During the topping andchopping LIP Of the debris none of the !,:oil on sto was disturbed, In fact the way
the debris %sas handled it rnay very well have helped the soil. Black berries grow in huge clumps and
shade out every IciAN growing plant where it invades. This shading kills the plants and their root systeirris.
The black berry for its part has a centras ClUrnp/root system and -then sends out several 1-0-20' canes that
over1ap themseNes to form thick mats, One ends Up With a V CWnips of roots and a space of 5-1.0' or
more before the next 1' ciurnp of roots. pn between the ground loses all other Wriding rinaterials/roots
through decay.
To address mitigation of the violaticirl 52 Red Aider sesi wouid be planted with .small areas of
grOUnd having t,o be cleared to assure the survivai of the seedlin,gs. in reality to assure the seedling
survival afl the remaining topped trees should be rernoved as they are and will continue to re-siorout and
fdl back in, there by shading out the seediings. These removals most assuredly wNI darnage the crIticai
area disturbing and exposing the fragile soil, The number of trees to be replanted over the r)Uffiber
topped (49) is to allow for a survival ratio and return'the historical site make up. Due to the past
encroachment of blackberry a Minimum of one site Ost a year wouW be, needed to cut back the rapid
growing blackberries and givethe seedlings a chance to re-establish the natLjral state of the parcel.
These site visits, may mead to (:;ontinuefor 6-7 years.
it is my opinion, experence and aCUA-,)i observation of this particular site that the topped alder trees wN
survive the topping and reforrn f0i canopies,
Pi of 2
In ciosing my professionall opinion is that this mitigation not be undertaken. I recommend that the trees
be correctiveiy pruned in 2-3 years to re-establish the central trunk one norrnaHy sees in this species and
then let them finish their He cycle as a rninirnum for action. This would be short of just letting the
natUra6 course of nature take place in the re -sprouting and establishment of the alder tops/ crowns with
no further disturbance of the site. A complete return to pre-cutting condition in 3-5 years versus the �.5--
20 for, the seedlings proposed.
The owner of this parcel will be instaHing no trespassing signs in the hopes of eliminating illegal Wtflr�g
and dUrnping in the -future.
RespeCtfUHY Submitted
q (,@ (/ 5-
Neal Baker
ArboHstsNW.com
ISA Cert PN1075A
ISA Tree Risk Assessment Qualified
PNW ISA CTRA #867
Member AREA & SOCA
IMPF
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Nguyen tree inventory
Parcel 00513105900606
Red Alder (Alnus rLibra) RA
Pacific WMowar (Sakxlucida) PW
EngHsh Hawthorne (Crataegus laevigata) EH
Diarneter at Breast Height (DBF-1)
Trees
1- 20" DBH RA 2 leaders 15' tall
2. 8" DBFi 15' tall
3. 68" DBH 6 Stem RA 15-17'tall
4. 13" DBH RA 1.5-17' tall
5, 14" DBFI RA 1547' Tail
6. 10" DBH RA 15 -17' -ran
7. 7" DBH RA 12' Tall
S. 23' DBH 3 stern RA 15-17' TA's
R. 8" DBH RA 15-17"FaH
M 1.2" DBH R .15-17' Tall
13_ 4" DBH PW 12' Tull M. smothered by Blackberries
12. 16" RA 15.1.7" Tall
11 13" BH 2 stern RA 15...17' Tall
14. 107"' DBH 28 stern RA
15. 8" DBH EH untOUched % covered by blackberry
Trees 3, 8 i3, 14 are actually clurnps of srnafler DBH, RA's, Example the 107"" of # 14 wot,M be
divided by 28 to get an average Of jUSt under 4" iridMdual DBH's.
Total nUmber of -trees to be replanted WOLM be 49 plus 5% which is just less than 3 trees for a
total to be repianted of 5Z Red Alder seedHngs,
In my professiona► opinion all the trees were heafthy .specimens and they will all survive the
topping.
Respectfufly Subni�tted
Neal Baker
Arborlstr>NW,com
lSA Cert PN1075A
lSA Tree Risk Assessment Quakfied
PNW ISTRA #867
Member AREA & SOCA
PI Of I