A letter from Gus Yaki to a proponent of Sea Buckthorn as a crop:
"While, as you state, it tastes good and is good for you, Sea Buckthorn really is BAD for the environment, here in North America. That is because, as you hinted, it is escaping into the natural environment, not only in Britain, but also here on the prairies, and, as a result, is destroying biodiversity.
For promoting wildlife, in North America, it is a disaster. Yes, the berries are eaten by Bohemian Waxwings and other birds in winter, but then they fly to the natural areas where they deposit the undigested seeds along with a packet of fertilizer. Those seeds readily germinate next spring. The seedlings, having no pathogens, parasites or predators, soon displace all the native vegetation which still has to contend with its own suite of bio-controls. Ultimately, there will be no native fruiting plants to provide winter food for the grouse or other wildlife which depend on them. So how is Sea Buckthorn helping biodiversity?
Of greatest significance is the fact that there are no insects that feed upon these plants here. Therefore as the native plants which co-evolved with local insects, etc. are displaced, there is no food for those birds species, etc., which are totally dependent upon insects as food for their young. This includes many precocial species of birds such as members of the Galliformes, and many altricial species, such as most of our Passerines. This is leading to a decline and ultimately total loss of many bird species. What it is doing to other life-forms is, as yet, unknown, but it could lead to a domino effect that could cause a total collapse of the ecosystem.
Here on the prairies, most of the Sea Buckthorn has escaped to the low-lying, moist, riparian areas, the richest of all in biodiversity. Where it is now established, it has turned these areas into a monoculture.
From a local wildlife point of view, such colonies are now virtually biological deserts.
When it grows along the riverbanks and islands, because it readily spreads by rhizomes, once germinated, a single seed is able to colonize an area of acres within a few years. Such areas soon become impenetrable thickets. They are so dense that little light reaches the ground, therefore all herbaceous plants disappear. The soil beneath them is now unprotected. During periods of flooding, this results in the loss of topsoil, and the silting of waterways, choking insect and fish habitat.
Rather than eliminating it, it is the cause of soil erosion here! In Calgary, we now have dozens of established colonies. Volunteers have been engaged in removing some of them, but most take several years to completely control, because if one section of a rhizome is overlooked, it readily rejuvenates the colony.
In river valley outside of urban centres, where volunteers will be few in number, one can ultimately expect to see the entire native riparian area displaced. Most municipalities do not have the funds to hire personnel to contend with this invader, let alone locate them..
If you ever get to Calgary on your work, I would be pleased to show you some of the established colonies and the problems that are being created. I'm afraid that with the release of this plant in North America, we have opened a Pandora's box. I'm sorry that you have given Sea Buckthorn such a glowing report with respect to North America. As you well know, invasive species, next to habitat loss, is the greatest cause of species extinction."