Here at the heart of the remote Upper Huallaga Valley, ridge after ridge is dotted with plots of coca plants - the world's largest supply of coca. In an uneasy alliance, heavily armed narco-traffickers and the Shining Path guerrillas control the region and what in sheer export revenue is Peru's leading industry.
In an effort to undercut the base of much of the cocaine flowing into the United States, the Reagan administration wants to begin an unprecedented aerial spraying of a poisonous herbicide, known as Spike, throughout this remote and rugged region. Critics and advocates agree that a blanket of poison would probably be the fastest way to kill the vast crop and destroy the economic base of the traffickers and the guerrillas.
But controversy over the environmental effects of such spraying has so far stalled the joint US-Peruvian herbicide program.
Meanwhile, despite other types of eradication efforts, the size of the coca crop is growing at an estimated 10 percent a year.
Manual eradication of the plants is costly and time consuming. Sometimes it takes two men to dig up a stubborn coca plant. And it is dangerous. In the past five years, the Shining Path guerrillas or drug traffickers have killed 34 people involved in eradication efforts or related crop-substitution programs. Only 800 acres of nearly 500,000 acres of coca under cultivation in Peru were manually destroyed in 1987, for example.
Large-scale herbicide use is considered a ``critical'' component of the US antinarcotics plan in Peru, a State Department narcotics division official says. ``It is considered a breakthrough, and without it you're basically going to have to do manual eradication. To eradicate just 10 percent of the crop would be just a holding action, because that's only [equal to] the growth.''
``If we use Spike, we'll get [financial] help'' from the US,'' reasons Gen. Juan Zarate, chief of Peru's police antidrug operations. His chief concern, he explains, is getting new equipment - arms and aircraft - to combat the narco-traffickers, who are better funded than Peru's police.
US-Peruvian testing of several herbicides, applied manually to small plots, started in Peru last October. US-contracted agricultural consultants reported that Spike, the trade name used by the Eli Lilly & Co. for tebuthiuron, showed early promise when grass begin growing on the test sites.
But aerial spray tests of Spike scheduled for this summer have been stalled because of the environmental controversy stirred by last spring's publicity about the program.
Both Peruvian and international environmentalists are concerned about the rapid deployment of the herbicide in the region without adequate environmental-impact studies. Concerns include long-term persistence of the herbicide in the soil, the chemical's movement in water runoff to other areas of the rain forest, and possible ``drift'' of the herbicide during aerial drops of the chemical pellets. Others suggest coca growers will only hopscotch to new areas, inviting a more widespread use of chemicals over time.
US sources counter that Spike's environmental destruction does not compare with the erosion and agrochemical damage caused by coca production. Further, they say, if Spike is used seriously enough in the first instance, coca growers will see the futility of trying to replant it.
Meanwhile, the Lilly company announced in May it would not sell Spike for coca eradication in Peru. US sources who are determined to forge ahead with Spike - and there is concern they may force Lilly legally to sell the chemical for the program - say the company is concerned about being held liable for any damages as well as concern over terrorist retaliation against its other business activities in Peru.
Though US State Department officials say they have Peru's support for the aerial spraying - and the drug police chief says he's determined to use the chemical - the controversy has political and economic effects for Peru's leaders.
Political observers here say the anti-narcotics issue has been the single issue on which President Al'an Garc'ia can act positively with the US to win new foreign aid. His independent style - particularly the limit he put on paying foreign debt - has been a diplomatic barrier.
Though environmental concerns over Spike have not been a major public issue here, it has become important for President Garc'ia, who is sensitive to keeping his independent image intact in his dealing with the Yankees.
``I'm completely prepared to implement whatever measures are necessary to stop and eradicate [coca],'' Mr. Garc'ia told US reporters who accompanied him on a tour of this region last month. ``Spike is an idea that can't be rejected but it must be studied. I understand very well the US urgency regarding herbicide. But we must have the right to say that those not under that urgency must be given a scientific ... answer'' regarding the safety of the herbicide.
Garc'ia also said there have only been ``limited'' efforts to substitute new crops for coca.
Local coca growers surrounding Uchiza gathered near the President's entourage to express their opposition to eradication efforts. Garc'ia said that because the coca crop is so much more lucrative than any alternative crop, greater economic aid is needed to help farmers.
``If a substantial portion of the [US] population is subsidizing [coca], why not subsidize some other crop?'' Garc'ia asked.
The herbicide controversy has caused divisions even among US officials.
Walter Gentner, a longtime US Department of Agriculture liaison to the State Department, resigned over the issue, because ``I was encouraged to bless the use of tebuthiuron in South America.''
``I'm not saying it's good or bad,'' he says of Spike. But the US plan to push Spike testing in Peru would bypass the US's normal two- or three-year environmental-impact study, he says. ``Why should we be any less careful in another country than we are in our own?''
Further, officials from the US Agency for International Development, assigned to find alternative crops for coca producers, criticize the Spike plan because the chemical could persist for up to 18 months in the soil and possibly prevent the planting of new, alternative crops.
``The object of the US government and [the object] so stated by the President [G'arcia] is to get rid of coca. That's first,'' says a US diplomat here. ``And if you allow all other considerations to come first, you avoid your own objective. You can even argue, `So what if a few little guys are inconvenienced if you're going to make a major dent in the cocaine trade?'''
But, says Peruvian economist Guido Pennano, ``you can't ask a country to stop feeding itself because it [cocaine] is impinging on you. Peru needs this $1.2 billion [coca industry] for survival, for the dollars we get.''
Without realistic economic programs to replace immediately the coca economy, he says, a political backlash from the lower classes will be felt. He says the chemical eradication program, without economic planning, will immediately strengthen the Shining Path terrorists, who have cast themselves as the protectors of the peasant coca growers.