|New Mexico Locust - Anza California|
The lady who now owns it is quite a collector of things. She runs an antique barn down in Anza. But the New Mexico Locusts which really don't get much higher than what you see in the picture
Black locust is native to the southern Appalachians and the Ozarks, where it occurs on slopes and forest edges. It has been planted in 48 states and was noted as spreading in jack pine barrens in Michigan as early as 1888. It tolerates a wide range of soil conditions, and spreads clonally as well as by seed. Its dense thickets shade out native vegetation. As a legume, black locust fixes nitrogen and soil nitrogen levels are higher under old trees. It produces more leaf litter and that litter has much higher nitrogen concentrations than most native tree species. Soils under black locust also have elevated levels of phosphorus and calcium.
Black locust is a deciduous, medium-sized tree ranging in height from 12-25 m (40-82 ft) and 30-60 cm (12-24 in) in diameter, although trees in Michigan have reached 1.5 m (5 ft) in diameter. It has a narrow crown and an open, irregular form with contorted branches. Black locust has an extensive network of lateral roots and forms dense clones.
Reproduction/Dispersal of Black Locust
Black locust reproduction is primarily vegetative, although it can also reproduce by seed. It sprouts from the roots and forms clones, particularly in sandy soils. It also sprouts easily from stumps in response to damage. Black locust grows rapidly and matures early; some trees may produce seed at six years of age. Heavy seed crops occur at one or two year intervals. The seeds have a hard, impermeable coat and require scarification to germinate. They are heavy and fall close to the parent tree, although birds may move them over longer distances. Michigan Flora notes that seeds may remain viable in the ground for up to 88 years. Seeds can accumulate in the soil a density of 29,817 seeds/acre in second-growth mixed forest. Densities are much lower in mature forest. Trees begin suckering at four or five years of age. A fibrous network of roots connects a black locust grove, with the oldest trees in the center and younger trees around the periphery, In late-successional communities, black locust becomes rare, as the species is shade-intolerant.
A more positive piece on Black Locust and Fire Ecology was from the University of Georgia
Soil nitrogen mineralisation and nitrification potentials, and soil solution chemistry were measured in Black Locust (Robinia pseudo-acacia L.), in pine-mixed hardwood stands on an early successional watershed (WS6), and in an older growth oak-hickory forest located on an adjacent, mixed hardwood watershed (WS14) at Coweeta Hydrologic laboratory, in the southern Appalachian mountains, U.S.A. Nitrification potentials were higher in black locust and pine-mixed hardwood early successional stands than in the oak-hickory forest of the older growth watershed. Ammonification rates were the main factor controlling nitrification in the early successional stands. There was no evidence of inhibition of nitrification in soils from the older growth oak-hickory forest site.
Within the early successional watershed, black locust sites had net mineralisation and nitrification rates at least twice as high as those in the pine mixed-hardwood stands. Concentrations of exchangeable nitrate in the soil of black locust stands were higher than in pine-mixed hardwoods at 0–15 cm in March and they were also higher at 0–15, 16–30 and 31–45 cm depth in the black locust dominated sites in July. Soil solution nitrate concentrations were higher under black locust than under pine-mixed hardwoods. Areas dominated by the nitrogen fixing black locust had greater nitrogen mineralisation and nitrification rates, resulting in higher potential for leaching losses of nitrate from the soil column in the early successional watershed."
So there are pros and cons to this beautiful tree. So what's new, most of the cons are a result of human ignorance and even stupidity. The tree has potential just as any other living thing on this planet. Depending on it's location around the globe it could enhance or becoming an uncontrollable overwhelming invasive. Please take a look below at some pictures of the trees along Hwy 67 that most motorists never give a second glance at. It's a pity really. They've truly beautified this location along Hwy 67 since the early 1960s. Back then I remember viewing them along Hwy 67 just past Poway road heading further east towards Ramona when we took weekend family drives to Julian and seeing these 15 or so single large trees. But that all change dramatically after the 2003 Cedar Fire which seemingly destroyed everything. I say seemingly because appearances above ground were deceiving. It was what was happening underground that made the incredible difference which was never evident for decades until tragedy struck.
The above photos show far far more young Black Locust trees, than were originally present before the fire. Rather than seed [which could also be a very real possibility], these trees most likely regenerated by vegetative sprouting from their extensive root system network infrastructure. The consequence of the 2003 Cedar Fire is now there are 10 times as many Black Locust trees [most likely clones] as previously present before the fire. Now mind you, you'll have to look closely as these little Locusts which are woven in among the Laurel Sumac, but they are everywhere far up the hill and grow right down to Hwy 67. What an incredible come back.
Below is an aerial photograph just after the 2003 Cedar fire which consumed this entire area. The Antique shop of course is obliterated and the hill where these masses of Black Locust trees are located is on the very far right where the Hay 67 ends at the photo to the right. You can also see the Iron Mountain Trail parking area across the street. Mount Woodson is over on the left, but out of the picture. They Hwy 67 on the left running towards Ramona at this point travels through some of the most beautiful old growth Oak Tree Chaparral mosaic you'll ever find and if Fire never hit this area EVER, it would still be healthy and perfect as it is.
|Photo: Gary Morris|
Below here is an excellent link for viewing aerial photographs of the 2003 Cedar Fire burn areas and the devastation left behind.
Black Locust at the end of the line of the #10 Trolley line at Guldheden between two apartment buildings in
the south of Göteborg Sweden. the south of Göteborg Sweden. For further info on Locust potential for rebuild the land, please see the article on New Mexico Locust.