Do you see ecological problem in Japan from this photo?
The area for Niiharu and Miho has the richest colony of ferns in Yokohama. Do you remember Miho Citizen Forest counts 100 kinds out of 600 known ferns in Japan? In Niiharu, the area surrounded by the route B-4 to 8 is a beloved place by botanists of major universities in Japan who are marveled by the level of conservation in the middle of highly developed suburban environment. Even though, it shows strain these days. The place is bordered by a narrow unpaved trekking road which separates at the ridge of a hill the forest from Kirigaoka Town 霧が丘. Kirigaoka is a completely developed suburban residential community. The standard issue in Yokohama between urbanites and forests always exists there. “Dark forest is scary.” “Lots of fallen leaves are nuisance.” Etc., etc. 10 years or so ago, the Residents’ Association of Kirigaoka, the Niiharu Council 新治保全管理計画協議会, and the City agreed to cut large trees along the border road in order to make more space between the houses and the Forest. Now we can see rays of sunshine and roofs of houses from the forest floor with ferns. The problem was solved for Kirigaoka. However …
this is the road between|
the “Jurassic” and “the 21st century suburbia.”
It’s certainly nice to have such an unpaved road
for cross-country training …
According to Dr. Kitagawa who presided this spring the volunteer training titled “30 Spring Flowers in the Forests of Yokohama,” the tree-cutting brought problems to the cedar / fern forest. She said, “Look. We can now see roofs of the houses from here. It means the winds can blow down from the ridge. Both cedar and ferns are humidity-loving vegetation. The dry winds from the housing area dissipate the moisture of the valley and change the ecology. Could you see the grasses growing between the ferns? They are invading the kingdom of ferns. It’s lamentable.” (I don’t think she used “deplorables” to express the situation …) It is true the place, especially near the housing, has fewer pteridophyta, but more of bushes of spermatophyte.
|Not so Jurassic … with sunshine anyway.|
The issue is a topic among Niiharu Lovers. The relatively new volunteers are a kind of impressed by the indication of Dr. Kitagawa who is an author for popularvisual dictionary of Japanese pteridophyta. “Yeah, broad-leaved evergreens are invading.” “Aucuba japonica is spreading, have you noticed?” “In the end, Niiharu is an island surrounded by the ocean of houses. The tree-cutting exacerbated the deterioration.” In contrast, those old guards are not convinced by her theory.
“Hey, the place has water sources, which must have connected to the 5 springs at the bottom of the valley in Rouba 篭場.” “Yeah, the drying of the place has been continuing for decades nonetheless. When the Citizen Forest began in 2000, the place was like that already.” “Winds caused by cutting several trees on the border few years back cannot cause a drastic change in the 1.5ha valley. The place has a complicated geography.” “Sure, those spermatophytes were already there before the operation.” The alternative theory about the desiccation is the housing development of Kirigaoka itself. The community was developed during the 1980s by Japan Housing Corp that was a half-governmental entity (; now it’s called UR, Urban Renaissance Agency). The Corp realized the western slope of the hill in Niiharu is ideally situated from Yokohama IC of Tomei Expressway, in addition to the not-so-far distance from Aobadai Station of Tokyu Denentoshi Line going directly to the center of Tokyo. They bulldozed the place for housing. The conjecture is, now the tree-less western slope cannot help the eastern side to hold water as before. “The streams running within the cedar forest are thinning every year.” “Have you noticed one of the 2 ponds along the road between B4 and B5? It’s shrinking these days.” “Yes, yes. Our plan to create a biotope for dragon flies there was scrapped consequently, do you remember?” “Yeah. Mr. X hand-dug the water way from the cedar valley for months in order for the biotope. Nothing came out from his toil.” Oh, my …
B5 to B4,|
the road is often muddy due to
the water from the cedar valley.
though, one of the ponds is shrinking.|
Could you see the wall of mud at the bottom of this picture?
That part was under water before.
In addition, the issue becomes complicated due to one of the landlords whose property is running a part of the border between the cedar / fern forest and the developed town. The title-holder is not an individual, but an incorporated educational institution, Horii Gakuen. They do not participate in the Niiharu Council so that they are not a part of coordination for forest management. They do not abide either by the understanding written in the Niiharu Conservation and Management Plan 新治保全管理計画 that is a gentlemen’s agreement anyway. The Lovers seniors said the institution did tree-cutting and weeding 6 or 7 years ago, but since then no maintenance work is present … It seems to me Niiharu Council is wondering how to approach to the school whose HDQ is in the downtown … It’s an example that forest management becomes complex when a property owner is not local, nor individual, and do not have much stake for the forest. At least in Niiharu, this tricky proprietor does not bulldoze the middle of the forest … I recalled the billboard-shouting match between a temple in downtown and the local community surrounding Shinbashi Citizen Forest.
up there on the left is|
the property of Horii Gakuen.
at the center of Shinbashi Forest last year.|
Sengenji Temple 浅間寺 from the downtown was
constructing cemetery that would divide
the Shinbashi Forest in half.
Having said that, the communication within the Niiharu Council may not be so easy either. I’ll report you further about the things of coordination in Niiharu next week.
|Everybody agrees this sign post needs renovation …|
If you find a problem in the Niiharu Forest, please make a contact with
Office for the Park Greeneries in the North 北部公園緑地事務所
Yokohama Municipal Government Creative Environment Policy Bureau 横浜市環境創造局
Phone: 045-311-2016 (I guess in Japanese only)
FAX: 045-316-8420 (I hope there is somebody who can read English …)
Niiharu Administrative Office / Satoyama Exchange Center 新治管理事務所・里山交流センター